Data processing method and apparatus

ABSTRACT

Embodiments of the present invention disclose a data processing method and apparatus, and belong to the field of communications technologies. The method includes: generating a physical layer protocol data unit PPDU, where the PPDU includes a preamble field, a data field, and a middle preamble field, and the preamble in the PPDU includes information used to indicate an insertion frequency of the middle preamble in the data field in the PPDU; and sending the PPDU. The insertion frequency of the middle preamble in the data field is indicated by using a specified field in the preamble. In this way, in different scenarios, the middle preamble may be inserted into the data field at different frequency, thereby reducing overheads of an inserted pilot and improving data transmission performance.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/537,219, filed on Aug. 9, 2019, which is a continuation ofInternational Application No. PCT/CN2018/094577, filed on Jul. 4, 2018.The International Application claims priority to Chinese PatentApplication No. 201710537942.7, filed on Jul. 4, 2017. All of theafore-mentioned patent applications are hereby incorporated by referencein their entireties.

TECHNICAL FIELD

The present invention relates to the field of communicationstechnologies, and in particular, to a data processing method andapparatus.

BACKGROUND

In a wireless local area network (WLAN), starting from 802.11a/g, anorthogonal frequency division multiplexing (OFDM) modulation scheme isused for a data packet (also referred to as a physical layer protocoldata unit (PPDU)), and an entire transmission bandwidth is allocated toone station (STA).

In 802.11ax, orthogonal frequency division multiple access (OFDMA) isfurther introduced based on OFDM, so that an entire bandwidth may beallocated to a plurality of STAs. 802.11ax defines four data packettypes, including a single user (SU) data packet, an extended rangesingle user (ER SU) data packet, a trigger-based (TB) data packet, and amulti-user (MU) data packet.

In a data transmission process in the wireless local area network, toresolve a problem of an excessively fast channel change caused by aDoppler scenario (a high-speed movement scenario), a middle preamble(Midamble) is inserted into a data field in the PPDU. To be specific, amidamble is inserted always every M symbols.

However, such a manner of inserting a midamble always every M symbols isdifficult to accommodate different Doppler scenarios and data modulationand coding schemes.

SUMMARY

Embodiments of the present invention provide a data processing methodand apparatus, to resolve a problem that an existing manner of insertinga midamble always every M symbols is difficult to accommodate differentDoppler scenarios and data modulation and coding schemes.

According to a first aspect, an embodiment of the present inventionprovides a data processing method, including: generating a physicallayer protocol data unit PPDU, where the PPDU includes a preamble field,a data field, and a middle preamble field, and the preamble in the PPDUincludes information used to indicate an insertion frequency of themiddle preamble in the data field in the PPDU; and sending the PPDU. Theinsertion frequency of the middle preamble in the data field isindicated by using a specified field in the preamble. In this way, indifferent scenarios, the middle preamble may be inserted into the datafield at different frequency, thereby reducing overheads of an insertedpilot and improving data transmission performance.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in one of the following fields: an SR field used to indicate aparameter related to spatial reuse in a high efficient signal field AHE-SIG-A, an MCS field used to indicate a modulation and coding schemein the HE-SIG-A, an MCS field in a high efficient signal field BHE-SIG-B, a SIGB MCS field used to indicate a high efficient signalfield B modulation and coding scheme in the HE-SIG-A, a combination ofan MCS field and a DCM field in the HE-SIG-A, a combination of an MCSfield and a DCM field in the HE-SIG-B, a combination of a SIGB MCS fieldand a SIGB DCM field in the HE-SIG-A, an NSTS field used to indicate aquantity of space time streams of a single user in the HE-SIG-B, acombination of an MCS field and an NSTS field, or an RU allocation fieldused to indicate a resource unit in the HE-SIG-B.

In a possible implementation, the insertion frequency of the middlepreamble is indicated by using one or more of reserved values of the SRfield.

In a possible implementation, the insertion frequency of the middlepreamble is indicated by using one or more of reserved values of the MCSfield or the SIGB MCS field.

In a possible implementation, the insertion frequency of the middlepreamble is implicitly indicated by using a parameter used to indicatean MCS in the MCS field.

In a possible implementation, the insertion frequency of the middlepreamble is indicated by using the combination of the MCS field and theDCM field.

In a possible implementation, the insertion frequency of the middlepreamble is indicated by using the combination of the SIGB MCS field andthe SIGB DCM field.

In a possible implementation, the insertion frequency of the middlepreamble is implicitly indicated by using a parameter used to indicatean NSTS in the NSTS field.

In a possible implementation, the insertion frequency of the middlepreamble is indicated by using the combination of the MCS field and theNSTS field.

In a possible implementation, the insertion frequency of the middlepreamble is indicated by using a reserved value of the RU allocationfield.

According to a second aspect, an embodiment of the present inventionprovides a data processing method, including: generating a triggerframe, where the trigger frame is used to instruct to generate and senda physical layer protocol data unit PPDU, the PPDU includes a data fieldand a middle preamble field, and the trigger frame includes informationused to indicate an insertion frequency of the middle preamble in thedata field in the PPDU; and sending the trigger frame. The insertionfrequency of the middle preamble in the data field is indicated by usinga specified field in the trigger frame. Based on the trigger frame, theTB PPDU may be triggered and the insertion frequency of the middlepreamble in the data field in the TB PPDU may be indicated. In this way,in different scenarios, the middle preamble may be inserted into thedata field at different frequency, thereby reducing overheads of aninserted pilot and improving data transmission performance in a PPDUtransmission process.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in one of the following fields: a Trigger Type field used toindicate a trigger frame type, a Doppler field used to indicate whethera Doppler mode is used for a data packet, an HE-SIG-A field, a TriggerDependent Common Info field for indicating common information based on atrigger frame type, an MCS field, a combination of an MCS field and aDCM field, an RU allocation field, an SS allocation field used toindicate a quantity of space time streams, or a combination of an SSallocation field and an MCS field in the trigger frame.

In a possible implementation, one or more of reserved values of theTrigger Type field in the trigger frame are set to indicate that thetrigger frame is a Doppler trigger frame, and to indicate that thetrigger-based TB PPDU uses a middle preamble structure, and theinsertion frequency of the middle preamble is indicated by using one ormore of reserved values of the HE-SIG-A field.

In a possible implementation, one or more of reserved values of theTrigger Type field in the trigger frame are set to indicate that thetrigger frame is a Doppler trigger frame, a midamble frequencyindication field is added to the Trigger Dependent Common Info field inthe trigger frame, and the insertion frequency of the middle preamble isindicated by using the midamble frequency indication field.

In a possible implementation, one or more of reserved values of theTrigger Type field in the trigger frame are set to indicate that thetrigger frame is a Doppler trigger frame, and the insertion frequency ofthe middle preamble is indicated by using one or more of reserved valuesof the MCS field.

In a possible implementation, one or more of reserved values of theTrigger Type field in the trigger frame are set to indicate that thetrigger frame is a Doppler trigger frame, and the insertion frequency ofthe middle preamble is indicated by using the combination of the MCSfield and the DCM field.

In a possible implementation, one or more of reserved values of theTrigger Type field in the trigger frame are set to indicate that thetrigger frame is a Doppler trigger frame, and the insertion frequency ofthe middle preamble is indicated by using a reserved value of the RUallocation field.

In a possible implementation, one or more of reserved values of theTrigger Type field in the trigger frame are set to indicate that thetrigger frame is a Doppler trigger frame, and the insertion frequency ofthe middle preamble is implicitly indicated by using a parameter used toindicate an SS in the SS allocation field.

In a possible implementation, one or more of reserved values of theTrigger Type field in the trigger frame are set to indicate that thetrigger frame is a Doppler trigger frame, and the insertion frequency ofthe middle preamble is implicitly indicated by using a parameter used toindicate an SS in the combination of the SS allocation field and the MCSfield.

In a possible implementation, the Doppler field in the trigger frame isset to 1 to indicate that the TB PPDU uses a midamble structure, and theinsertion frequency of the middle preamble is indicated by using one ormore of reserved values of the HE-SIG-A field in a common field.

In a possible implementation, the Doppler field in the trigger frame isset to 1, a midamble frequency indication field is added to the TriggerDependent Common Info field in the trigger frame in a common field, andthe insertion frequency of the middle preamble is indicated by using themidamble frequency indication field.

In a possible implementation, the Doppler field in the trigger frame isset to 1, and the insertion frequency of the middle preamble isindicated by using one or more of reserved values of the MCS field.

In a possible implementation, the Doppler field in the trigger frame isset to 1, and the insertion frequency of the middle preamble isindicated by using the combination of the MCS field and the DCM field.

In a possible implementation, the Doppler field in the trigger frame isset to 1, and the insertion frequency of the middle preamble isindicated by using a reserved value of the RU allocation field.

In a possible implementation, the Doppler field in the trigger frame isset to 1, and the SS allocation field is used to indicate the insertionfrequency of the middle preamble while indicating an SS parameter.

In a possible implementation, the Doppler field in the trigger frame isset to 1, and the insertion frequency of the middle preamble isimplicitly indicated by using a parameter used to indicate an SS in thecombination of the SS allocation field and the MCS field.

In a possible implementation, the insertion frequency of the middlepreamble is indicated by using one or more of reserved values of theHE-SIG-A field.

In a possible implementation, the insertion frequency of the middlepreamble is indicated by using a reserved value of a Reserved field in aUser Info field.

According to a third aspect, an embodiment of the present inventionprovides a data processing method, including: generating a Media AccessControl MAC frame, where the MAC frame is used to instruct to generateand send a physical layer protocol data unit PPDU, the PPDU includes adata field and a middle preamble field, and the MAC frame includesinformation used to indicate an insertion frequency of the middlepreamble in the data field in the PPDU; and sending the MAC frame. Theinsertion frequency of the middle preamble is indicated by using aspecified field in the MAC frame. Based on the MAC frame, the TB PPDUmay be triggered and the insertion frequency of the middle preamble inthe data field in the TB PPDU may be indicated. In this way, indifferent scenarios, the middle preamble may be inserted into the datafield at different frequency, thereby reducing overheads of an insertedpilot and improving data transmission performance in a PPDU transmissionprocess.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in a high throughput control field HTC in the MAC frame, andthe HTC field includes an RU allocation field used to indicate aresource unit, a UL MCS field used to indicate an uplink modulation andcoding scheme, and a reserved value field Reserved.

In a possible implementation, the insertion frequency of the middlepreamble in the data field in the TB PPDU is indicated by using areserved value of the RU allocation field.

In a possible implementation, the insertion frequency of the middlepreamble in the data field in the TB PPDU is indicated by using one ormore of reserved values of the UL MCS field.

In a possible implementation, the insertion frequency of the middlepreamble in the data field in the TB PPDU is indicated by using one ormore of reserved values of the Reserved field.

According to a fourth aspect, an embodiment of the present inventionprovides a data processing method, including: receiving a physical layerprotocol data unit PPDU. The PPDU includes a preamble field, a datafield, and a middle preamble field, and the preamble in the PPDUincludes information used to indicate an insertion frequency of themiddle preamble in the data field in the PPDU.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in one of the following fields: an SR field used to indicate aparameter related to spatial reuse in a high efficient signal field AHE-SIG-A, an MCS field used to indicate a modulation and coding schemein the HE-SIG-A, an MCS field in a high efficient signal field BHE-SIG-B, a SIGB MCS field used to indicate a high efficient signalfield B modulation and coding scheme in the HE-SIG-A, a combination ofan MCS field and a DCM field in the HE-SIG-A, a combination of an MCSfield and a DCM field in the HE-SIG-B, a combination of a SIGB MCS fieldand a SIGB DCM field in the HE-SIG-A, an NSTS field used to indicate aquantity of space time streams of a single user in the HE-SIG-B, acombination of an MCS field and an NSTS field, or an RU allocation fieldused to indicate a resource unit in the HE-SIG-B.

According to a fifth aspect, an embodiment of the present inventionprovides a data processing method, including: receiving a trigger frame,where the trigger frame is used to instruct to generate and send aphysical layer protocol data unit PPDU, the trigger frame includesinformation used to indicate an insertion frequency of a middle preamblein a data field in the PPDU, and the PPDU includes the data field andthe middle preamble field; generating the PPDU based on the triggerframe; and sending the PPDU.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in one of the following fields: a Trigger Type field used toindicate a trigger frame type, a Doppler field used to indicate whethera Doppler mode is used for a data packet, a high efficient signal fieldA HE-SIG-A, a Trigger Dependent Common Info field for indicating commoninformation based on a trigger frame type, an MCS field used to indicatea modulation and coding scheme, a combination of an MCS field and a DCMfield, an RU allocation field used to indicate a resource unit, an SSallocation field used to indicate a quantity of space time streams, or acombination of an SS allocation field and an MCS field in the triggerframe.

According to a sixth aspect, an embodiment of the present inventionprovides a data processing method, including: receiving a Media AccessControl MAC frame, where the MAC frame is used to instruct to generateand send a physical layer protocol data unit PPDU, the PPDU includes adata field and a middle preamble field, and the MAC frame includesinformation used to indicate an insertion frequency of the middlepreamble in the data field in the PPDU; and generating and sending thePPDU based on the MAC frame.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in a high throughput control field HTC in the MAC frame, andthe HTC field includes an RU allocation field used to indicate aresource unit, a UL MCS field used to indicate an uplink modulation andcoding scheme, and a reserved value field Reserved.

According to a seventh aspect, an embodiment of the present inventionprovides a data processing apparatus, including: a PPDU generation unit,configured to generate a physical layer protocol data unit PPDU, wherethe PPDU includes a preamble field, a data field, and a middle preamblefield, and the preamble in the PPDU includes information used toindicate an insertion frequency of the middle preamble in the data fieldin the PPDU; and a sending unit, configured to send the PPDU.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in one of the following fields: an SR field used to indicate aparameter related to spatial reuse in a high efficient signal field AHE-SIG-A, an MCS field used to indicate a modulation and coding schemein the HE-SIG-A, an MCS field in a high efficient signal field BHE-SIG-B, a SIGB MCS field used to indicate a high efficient signalfield B modulation and coding scheme in the HE-SIG-A, a combination ofan MCS field and a DCM field in the HE-SIG-A, a combination of an MCSfield and a DCM field in HE-SIG-B, a combination of a SIGB MCS field anda SIGB DCM field in the HE-SIG-A, an NSTS field used to indicate aquantity of space time streams of a single user in the HE-SIG-B, acombination of an MCS field and an NSTS field, or an RU allocation fieldused to indicate a resource unit in the HE-SIG-B.

According to an eighth aspect, an embodiment of the present inventionprovides a data processing apparatus, including: a trigger framegeneration unit, configured to generate a trigger frame, where thetrigger frame is used to instruct to generate and send a physical layerprotocol data unit PPDU, the PPDU includes a data field and a middlepreamble field, and the trigger frame includes information used toindicate an insertion frequency of the middle preamble in the data fieldin the PPDU; and a sending unit, configured to send the trigger frame.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in one of the following fields: a Trigger Type field used toindicate a trigger frame type, a Doppler field used to indicate whethera Doppler mode is used for a data packet, a high efficient signal fieldA HE-SIG-A, a Trigger Dependent Common Info field for indicating commoninformation based on a trigger frame type, an MCS field used to indicatea modulation and coding scheme, a combination of an MCS field and a DCMfield, an RU allocation field used to indicate a resource unit, an SSallocation field used to indicate a quantity of space time streams, or acombination of an SS allocation field and an MCS field in the triggerframe.

According to a ninth aspect, an embodiment of the present inventionprovides a data processing apparatus, including: a MAC frame generationunit, configured to generate a Media Access Control MAC frame, where theMAC frame is used to instruct to generate and send a physical layerprotocol data unit PPDU, the PPDU includes a data field and a middlepreamble field, and the MAC frame includes information used to indicatean insertion frequency of the middle preamble in the data field in thePPDU; and a sending unit, configured to send the MAC frame.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in a high throughput control field HTC in the MAC frame, andthe HTC field includes an RU allocation field used to indicate aresource unit, a UL MCS field used to indicate an uplink modulation andcoding scheme, and a reserved value field Reserved.

According to a tenth aspect, an embodiment of the present inventionprovides a data processing apparatus, including a receiving unit,configured to receive a physical layer protocol data unit PPDU. The PPDUincludes a preamble field, a data field, and a middle preamble field,and the preamble in the PPDU includes information used to indicate aninsertion frequency of the middle preamble in the data field in thePPDU.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in one of the following fields: an SR field used to indicate aparameter related to spatial reuse in a high efficient signal field AHE-SIG-A, an MCS field used to indicate a modulation and coding schemein the HE-SIG-A, an MCS field in a high efficient signal field BHE-SIG-B, a SIGB MCS field used to indicate a high efficient signalfield B modulation and coding scheme in the HE-SIG-A, a combination ofan MCS field and a DCM field in the HE-SIG-A, a combination of an MCSfield and a DCM field in the HE-SIG-B, a combination of a SIGB MCS fieldand a SIGB DCM field in the HE-SIG-A, an NSTS field used to indicate aquantity of space time streams of a single user in the HE-SIG-B, acombination of an MCS field and an NSTS field, or an RU allocation fieldused to indicate a resource unit in the HE-SIG-B.

According to an eleventh aspect, an embodiment of the present inventionprovides a data processing apparatus, including: a receiving unit,configured to receive a trigger frame, where the trigger frame is usedto instruct to generate and send a physical layer protocol data unitPPDU, the trigger frame includes information used to indicate aninsertion frequency of a middle preamble in a data field in the PPDU,and the PPDU includes the data field and the middle preamble field; aPPDU generation unit, configured to generate the PPDU based on thetrigger frame; and a sending unit, configured to send the PPDU.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in one of the following fields: a Trigger Type field used toindicate a trigger frame type, a Doppler field used to indicate whethera Doppler mode is used for a data packet, a high efficient signal fieldA HE-SIG-A, a Trigger Dependent Common Info field for indicating commoninformation based on a trigger frame type, an MCS field used to indicatea modulation and coding scheme, a combination of an MCS field and a DCMfield, an RU allocation field used to indicate a resource unit, an SSallocation field used to indicate a quantity of space time streams, or acombination of an SS allocation field and an MCS field in the triggerframe.

According to a twelfth aspect, an embodiment of the present inventionprovides a data processing apparatus, including: a receiving unit,configured to receive a Media Access Control MAC frame, where the MACframe is used to instruct to generate and send a physical layer protocoldata unit PPDU, the PPDU includes a data field and a middle preamblefield, and the MAC frame includes information used to indicate aninsertion frequency of the middle preamble in the data field in thePPDU; a PPDU generation unit, configured to generate the PPDU based onthe MAC frame; and a sending unit, configured to send the PPDU.

In a possible implementation, the information used to indicate theinsertion frequency of the middle preamble in the data field in the PPDUis added in a high throughput control field HTC in the MAC frame, andthe HTC field includes an RU allocation field used to indicate aresource unit, a UL MCS field used to indicate an uplink modulation andcoding scheme, and a reserved value field Reserved.

According to a thirteenth aspect, an embodiment of the present inventionprovides a computer-readable storage medium. The computer-readablestorage medium stores an instruction. When running on a computer, theinstruction enables the computer to perform the methods according to theforegoing aspects.

According to a fourteenth aspect, an embodiment of the present inventionprovides a computer program product including an instruction. Whenrunning on a computer, the computer program product enables the computerto perform the methods according to the foregoing aspects.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of an application scenario according to anembodiment of the present invention;

FIG. 2 is a schematic structural diagram of an MU PPDU in the prior art;

FIG. 3 is a schematic diagram of a frame structure of a trigger frame inthe prior art;

FIG. 4 a is a schematic structural diagram of an SU/ER SU PPDU accordingto an embodiment of the present invention;

FIG. 4 b is another schematic structural diagram of an SU/ER SU PPDUaccording to an embodiment of the present invention;

FIG. 4 c is a schematic structural diagram of an MU PPDU according to anembodiment of the present invention;

FIG. 4 d is another schematic structural diagram of an MU PPDU accordingto an embodiment of the present invention;

FIG. 5 is an interaction diagram of a data processing method accordingto an embodiment of the present invention;

FIG. 6 is a schematic diagram of a communications system according to anembodiment of the present invention;

FIG. 7 is a structural diagram of a data processing apparatus accordingto an embodiment of the present invention;

FIG. 8 is a structural diagram of hardware of a data processingapparatus according to an embodiment of the present invention;

FIG. 9 is a structural diagram of another data processing apparatusaccording to an embodiment of the present invention;

FIG. 10 is a structural diagram of hardware of another data processingapparatus according to an embodiment of the present invention;

FIG. 11 is an interaction diagram of a data processing method accordingto an embodiment of the present invention;

FIG. 12 is a schematic diagram of a first frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 13 is a schematic diagram of a second frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 14 is a schematic diagram of a third frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 15 is a schematic diagram of a fourth frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 16 is a schematic diagram of a fifth frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 17 is a schematic diagram of a sixth frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 18 is a schematic diagram of a seventh frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 19 is a schematic diagram of an eighth frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 20 is a schematic diagram of a ninth frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 21 is a schematic diagram of a tenth frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 22 is a schematic diagram of an eleventh frame structure of atrigger frame according to an embodiment of the present invention;

FIG. 23 is a schematic diagram of a twelfth frame structure of a triggerframe according to an embodiment of the present invention;

FIG. 24 is a schematic diagram of a thirteenth frame structure of atrigger frame according to an embodiment of the present invention;

FIG. 25 is a schematic diagram of a fourteenth frame structure of atrigger frame according to an embodiment of the present invention;

FIG. 26 is a structural diagram of a data processing apparatus accordingto an embodiment of the present invention;

FIG. 27 is a structural diagram of hardware of a data processingapparatus according to an embodiment of the present invention;

FIG. 28 is a structural diagram of another data processing apparatusaccording to an embodiment of the present invention;

FIG. 29 is a structural diagram of hardware of another data processingapparatus according to an embodiment of the present invention;

FIG. 30 is an interaction diagram of a data processing method accordingto an embodiment of the present invention;

FIG. 31 is a schematic structural diagram of an HTC field in a MAC framein the prior art;

FIG. 32 is a first schematic structural diagram of an HTC field in a MACframe according to an embodiment of the present invention;

FIG. 33 is a second schematic structural diagram of an HTC field in aMAC frame according to an embodiment of the present invention;

FIG. 34 is a third schematic structural diagram of an HTC field in a MACframe according to an embodiment of the present invention;

FIG. 35 is a structural diagram of a data processing apparatus accordingto an embodiment of the present invention;

FIG. 36 is a structural diagram of hardware of a data processingapparatus according to an embodiment of the present invention;

FIG. 37 is a structural diagram of another data processing apparatusaccording to an embodiment of the present invention; and

FIG. 38 is a structural diagram of hardware of another data processingapparatus according to an embodiment of the present invention.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

To make the objectives, technical solutions, and advantages of theembodiments of the present invention clearer, the following clearlydescribes the technical solutions in the embodiments of the presentinvention with reference to the accompanying drawings in the embodimentsof the present invention. Apparently, the described embodiments are somebut not all of the embodiments of the present invention. All otherembodiments obtained by a person of ordinary skill in the art based onthe embodiments of the present invention without creative efforts shallfall within the protection scope of the present invention.

To facilitate understanding of the embodiments of the present invention,the following further explains the specific embodiments with referenceto the accompanying drawings, and the embodiments do not constitute alimitation on the embodiments of the present invention.

The embodiments of the present invention are mainly applied to datacommunication between one node and one or more other nodes, and in adata communication process, a Doppler scenario or a high-speed movementscenario occurs. For example, communication between an AP and a STAshown in FIG. 1 is also applicable between an AP and an AP or between aSTA and a STA. The data communication in FIG. 1 includes two types ofdata: uplink data (data sent by the STA to the AP) and downlink data(data sent by the AP to the STA). An 802.11ax standard defines four datapacket structures. For uplink and downlink single-user datatransmission, an SU PPDU or an ER SU PPDU is usually used fortransmission. For downlink multi-user data transmission, an MU PPDU isused for transmission. For uplink multi-user data transmission, first,the AP needs to send a trigger frame to the STA, and then the STA sendsa TB PPDU to the AP based on the trigger frame. FIG. 2 shows a form ofan MU PPDU in the prior art. As shown in FIG. 2 , the MU PPDU includes apreamble field, a data field Data, a middle preamble field Midamble, anda data packet extension field PE.

In a less desirable implementation, to resolve a problem of anexcessively fast channel change caused by the Doppler scenario (thehigh-speed movement scenario), a middle preamble field (Midamble) isusually inserted into the data field Data always every M symbols. Themiddle preamble field (Midamble field) may be a combination of HE-STFand HE-LTF or only HE-LTF. In a data receiving process, a midamble mayenable a receive end to re-estimate a channel after receiving data Dataof every M symbols, and then continue to receive data Data of next Msymbols, so as to effectively resolve the problem of the excessivelyfast channel change caused by Doppler. In the MU PPDU shown in FIG. 2 ,two midambles are inserted.

The preamble field includes a legacy preamble (L-Preamble), a repeatedlegacy signal field (RL-SIG), a high efficient signal field A(HE-SIG-A), a high efficient signal field B (HE-SIG-B), a high efficientshort training field (HE-STF), and a high efficient long training field(HE-LTF). It should be noted that, HE in the foregoing fields representsa reference number of the 802.11ax standard. In the solutions of thepresent invention, these fields may alternatively use another referencenumber to represent signal fields in a PPDU in another standard, such asnext generation (NG) and very high efficient (VHE).

TABLE 1 Field Full Name Meaning UL/DL Uplink/ Used to indicate whether adata Downlink packet is used for uplink transmission or downlinktransmission SIGB MCS HE-SIG-B High efficient signal field B Modulationand modulation and coding scheme Coding Scheme SIGB DCM HE-SIG-B Used toindicate whether dual Dual Coding carrier modulation is used for aModulation high efficient signal field B BSS color Basic Service Used toidentify a color of a Set Color basic service set Spatial reuse Used toindicate a parameter related to spatial reuse Bandwidth Used to indicatea bandwidth of a data packet Number of HE- MU MIMO: Used to indicate aquantity of SIG-B symbols or Multiple User symbols in a high efficientsignal MU-MIMO users Multiple Input field B or a quantity of users forMultiple Output multi-user multiple-input multiple-output SIGBcompression Used to indicate whether a high efficient signal field B iscompressed GI + LTF size Guard Used to indicate a Interval + High guardinterval and a size of a Efficient high efficient long Long Trainingtraining field Field size Doppler Used to indicate whether a Dopplermode is used for a data packet TXOP Transmit Used to indicate a transmitOpportunity opportunity Reserved Reserved bit, which is set to 1 Numberof HE-LTF Used to indicate a quantity of Symbols symbols in a highefficient long training field LDPC Extra LDPC: Low Used to indicatewhether an Symbol Segment Density Parity extra symbol segment Codeexists in a case of a low density parity code STBC Space Time Indicatewhether space time Block Code coding is used Pre-FEC Padding FEC:forward Used to indicate a padding factor Factor error control beforeforward error control PE Disambiguity PE: Data packet extension PacketExtension disambiguation bit CRC Cyclic Cyclic redundancy coderedundancy code Tail Tail bit

Referring to Table 1, Table 1 shows fields included in the HE-SIG-A inthe MU PPDU. The fields included in the HE-SIG-A include commoninformation, for example, identification information of a basic serviceset, indication information of a transmit opportunity, indicationinformation of a spatial reuse parameter, and allocation information ofsome resources on a physical layer. The allocation information of someresources on the physical layer includes related indication informationof a size of the HE-LTF, a quantity of HE-LTFs, a size of a guardinterval, an LDPC, and an STBC, and related information of the HE-SIG-B.The related information of the HE-SIG-B includes an MCS and a length ofthe HE-SIG-B.

The HE-SIG-B following the HE-SIG-A includes a common field and a UserInfo field. The common field is used to indicate resource unitallocation (RU Allocation). The RU allocation is used to indicateallocation of all resource units in frequency domain and a quantity ofSTAs in each resource unit. In 802.11ax, if the quantity of STAs in theresource unit is 1, a non-MU-MIMO mode is used, and if the quantity ofSTAs in the resource unit is greater than 1, a MU-MIMO mode is used.Depending on whether MU-MIMO is used for a resource unit, two differentindication methods are used for the User Info field in the HE-SIG-B.

TABLE 2 STA-ID STA Identifier The station identifier is usually used toindicate an association identifier of a STA. NSTS Number of Space Usedto indicate a quantity of Time Stream space time streams of a singleuser Tx Transmit Used to indicate whether a Beamforming Beamformingbeamforming technology is used MCS Modulation and Modulation and CodingScheme coding scheme DCM Dual Coding Dual carrier modulation ModulationCoding Indicate a coding type

Table 2 shows fields included in the User Info field in the HE-SIG-B ina case of the non-MU-MIMO mode.

TABLE 3 STA-ID STA Identifier The station identifier is usually used toindicate an association identifier of a STA. Spatial Number of A tableis used to indicate Configuration Spatial Stream a quantity of spacetime streams of an MU-MIMO unit. MCS Modulation and Modulation andcoding scheme Coding Scheme DCM Dual Coding Dual carrier modulationModulation Coding Indicate a coding type

Table 3 shows fields included in the User Info field in the HE-SIG-B ina case of the MU-MIMO mode.

TABLE 4 Doppler Condition/MCS MCS₀ MCS₁ MCS₃ MCS₅ 60 Km/h 50 30 15 8 on2nd/3rd tap 60 Km/h 30 20 10 5 on all taps 30 Km/h 60 40 20 10 on alltaps 15 Km/h 120 80 40 20 on all taps

Table 4 shows suggested midamble insertion frequency in cases ofdifferent rates and different MCSs. It can be learned from Table 4 thatin different Doppler scenarios and MCSs, a manner of inserting amidamble always every M symbols cannot be applied to differentscenarios.

TABLE 5 Field Full Name Meaning in Chinese Format Used to indicatewhether a format of a data packet is an SU format or a TB format Beamchange Indicate whether a beam change is used UL/DL Uplink/Downlink Usedto indicate whether a data packet is used for uplink transmission ordownlink transmission MCS Modulation and Modulation and coding schemeCoding Scheme for a data part DCM Dual Coding Used to indicate whetherdual Modulation carrier modulation is used for a data part BSS colorBasic Service Used to identify a color of a basic Set Color service setReserved Reserved bit, which is set to 1 Spatial reuse Used to indicatea parameter related to spatial reuse Bandwidth Used to indicate abandwidth of a data packet GI + LTF size Guard Interval + Used toindicate a guard interval High Efficient Long and a size of a highefficient long Training Field size training field NSTS Number of SpaceUsed to indicate a quantity of Time Stream space time streams TXOPTransmit Used to indicate a transmit Opportunity opportunity CodingIndicate a coding type LDPC Extra LDPC: Low Density Used to indicatewhether an extra Symbol Parity Code symbol segment exists in a case ofSegment a low density parity code STBC Space Time Indicate whether spacetime Block Code coding is used Pre-FEC FEC: forward Used to indicate apadding factor Padding error control before forward error control FactorPE PE: Packet Data packet extension Disambiguity Extensiondisambiguation bit Reserved Reserved bit, which is set to 1 Doppler Usedto indicate whether a Doppler mode is used for a data packet CRC Cyclicredundancy Cyclic redundancy code code Tail Tail bit

Comparing with a format of the MU PPDU, formats of the SU PPDU, the ERSU PPDU, and the TB PPDU lack the HE-SIG-B field. For example, Table 5shows fields included in the HE-SIG-A in the SU PPDU or the ER SU PPDU.For details, refer to the foregoing descriptions of the MU PPDU, anddetails are not described herein again.

FIG. 3 is a schematic diagram of a frame structure of a trigger frame inthe prior art. For uplink multi-user transmission, first, an AP sends atrigger frame to a plurality of STAs. The trigger frame may indicateresource for performing uplink transmission by a STA. After receivingthe trigger frame, the STA performs uplink multi-user transmission basedon the resource indication information in the trigger frame. The uplinkmulti-user transmission is performed based on the trigger frame.Therefore, a PPDU sent by the STA is referred to as a trigger-based datapacket structure (TB PPDU). The frame structure of the trigger framedefined in 802.11ax is shown in FIG. 3 , and includes a common field anda User Info field. The common field includes a trigger frame type usedto indicate trigger frames of different subtypes and carrier sensing(CS) required used to indicate whether the STA needs to perform carriersensing after receiving a trigger frame. Data is sent when a channel isidle. Depending on different trigger frame types, common information orstation information based on the trigger frame type carriescorresponding indication information. The User Info field includes RUAllocation, MCS, DCM, and SS Allocation.

The embodiments of the present invention provide a data processingmethod. The method relates to PPDU transmission. The method isapplicable to downlink data transmission (for example, the AP transmitsdata to the STA in FIG. 1 ) and uplink single user transmission (forexample, one STA transmits data to the AP in FIG. 1 ), and morespecifically, to transmission of an HE SU PPDU, an HE ER SU PPDU, and anHE MU SU PPDU. Specifically, the following content is included:

FIG. 5 is an interaction diagram of a data processing method accordingto an embodiment of the present invention. The method is applicable to aDoppler scenario or a high-speed movement scenario. A STA generates aPPDU (a Doppler bit field in a preamble in the PPDU needs to be set to 1in a PPDU generation process). FIG. 4 a is a schematic structuraldiagram of an SU/ER SU PPDU according to an embodiment of the presentinvention. The PPDU includes a preamble field, a data field, and amiddle preamble field, and the preamble field in the PPDU includesinformation used to indicate an insertion frequency of the middlepreamble field inserted in the data field in the PPDU. In thisembodiment of the present invention, a midamble is inserted every Msymbols (herein, the M symbols do not include the midamble) in the datafield. In the PPDU generation process, the STA first generates apreamble field part of the PPDU, and generates a data field part in theforegoing manner of inserting a midamble every M symbols in the datafield, so as to generate the entire PPDU. The STA sends the generatedPPDU to an AP. The AP receives the PPDU sent by the STA. When the APreceives the PPDU, the AP first receives the preamble field part of thePPDU, next obtains information M of the insertion frequency of themiddle preamble field inserted in the data field based on the preamblefield part, and then receives the data field part based on M.Specifically, the AP first receives data of M symbols in the data fieldbased on HE-STF and HE-LTF in the last part of the preamble field, andthen re-estimates a channel based on the midamble (HE-LTF or acombination of HE-STF and HE-LTF), and further receives data of next Msymbols. In this way, the AP receives the data field in the entire PPDU.

FIG. 4 b is another schematic structural diagram of an SU/ER SU PPDUaccording to an embodiment of the present invention. The PPDU includes apreamble field, a data field, and a middle preamble field. In the datafield Data, for every M symbols (herein, the M symbols include amidamble), that is, the M symbols include data and a midamble, themidamble has two formats: HE-LTF or a combination of HE-STF and HE-LTF.HE-LTF is one symbol, and a quantity of symbol in HE-STF is determinedbased on the preamble. In this embodiment, it is assumed that HE-STF isN symbols. When the midamble is HE-LTF, the M symbols include data ofM-1 symbols and HE-LTF of one symbol. When the midamble is a combinationof HE-STF and HE-LTF, the M symbols include data of M-N-1 symbols,HE-STF of N symbols, and HE-LTF of one symbol.

FIG. 4 c is a schematic structural diagram of an MU PPDU according to anembodiment of the present invention. For the PPDU, a midamble isinserted every M symbols (herein, the M symbols do not include themidamble) in the data field Data. For details, refer to relateddescriptions of FIG. 4 a , and details are not described herein again.

FIG. 4 d is another schematic structural diagram of an MU PPDU accordingto an embodiment of the present invention. For the PPDU, a midamble isinserted every M symbols (herein, the M symbols include the midamble) inthe data field Data. For details, refer to related descriptions of FIG.4 b , and details are not described herein again.

It should be noted that in this embodiment of the present invention,insertion of the middle preamble into the data field Data based onsymbols is described. Herein, in addition to symbol-based division, themiddle preamble may be inserted into the data field according to anotherrule, and details are not further described in this embodiment.

The information used to indicate the insertion frequency of the middlepreamble in the data field in the PPDU may be added in a spatial reuse(SR for short below) field in the HE-SIG-A (the HE SU PPDU, the HE ER SUPPDU, and the HE MU SU PPDU). For details, refer to Table 6. In an802.11ax standard, the SR field includes four bits, and may indicate 16cases (SR values are 0 to 15). When an SR value is 0, it indicatesSRP_DISALLOW, representing that SR transmission based on a spatial reuseparameter (Spatial Reuse Parameter, SRP) is prohibited. When SR valuesare 1 to 12, the values are reserved values. When an SR value is 13, itindicates SR_RESTRICTED, representing that SR transmission isrestricted. When an SR value is 14, it indicates SR_DELAY, representingthat SR transmission is delayed. When an SR value is 15, it indicatesSRP_AND_NON-SRG_OBSS-PD_PROHIBITED, representing that overlapping basicservice set (OBSS)-data packet detection for SRP and a non-SR group(Group) is prohibited.

TABLE 6 SR Value Meaning 0 SRP_DISALLOW 1-12 Reserved 13 SR_RESTRICTED14 SR_DELAY 15 SRP_AND_NON-SRG_OBSS-PD_PROHIBITED

Optionally, in an example of the present invention, the insertionfrequency of the middle preamble in the data field in the PPDU isindicated by using one or more of reserved values of the SR field. Thatis, the insertion frequency of the middle preamble is indicated by usingone or more of the reserved values (1 to 12) of the SR field. This maybe applicable to a downlink data transmission solution (for example, theAP transmits data to the STA in FIG. 1 ).

TABLE 7 SR Value Meaning 0 SRP_DISALLOW 1 M = M1 2 M = M2 3-12 Reserved13 SR_RESTRICTED 14 SR_DELAY 15 SRP_AND_NON-SRG_OBSS-PD_PROHIBITED

For example, Table 7 is an example of the foregoing indication method.The SR value 1 indicates M (the insertion frequency of the middlepreamble in the data field, that is, a middle preamble is inserted everyM symbols)=M1. The SR value 2 indicates M=M2. For example, M1=5, andM2=10. A specific quantity of values in the SR values 1 to 12 that areused to indicate M and a specific numerical value of M may be setaccording to a specific Doppler scenario or high-speed movementscenario, and this embodiment imposes no specific limitation thereon.

Optionally, in an example of the present invention, the insertionfrequency of the middle preamble in the data field in the PPDU isimplicitly indicated by using a parameter used to indicate SR in SR.This may be applicable to a downlink data transmission solution (forexample, the AP transmits data to the STA in FIG. 1 ).

TABLE 8 SR Value Meaning 0 SRP_DISALLOW, M = M1 1 SRP_DISALLOW, M = M2 2M = M1 3 M = M2 4-9 Reserved 10 SR_RESTRICTED, M = M2 11 SR_DELAY, M =M2 12 SRP_AND_NON-SRG_OBSS-PD_PROHIBITED, M = M2 13 SR_RESTRICTED, M =M1 14 SR_DELAY, M = M1 15 SRP_AND_NON-SRG_OBSS-PD_PROHIBITED, M = M1

For example, Table 8 is an example of the foregoing indication method.When the SR value is 0, 13, 14, or 15, the SR value indicates M=M1 whileindicating a corresponding SR parameter. Four values are randomlyselected from the SR values 1 to 12, and the four values each are usedto indicate M while indicating a corresponding parameter M=when the SRvalues are 0, 13, 14, and 15. For example, when the SR value is 1, itindicates SRP_DISALLOW and M=M2. The SR value 2 indicates M=M1. The SRvalue ₃ indicates M=M2. When the SR value is 2 or 3 only M is indicated,and the SR parameter is not indicated. When the SR value is 10, itindicates SR_RESTRICTED and M=M2. When the SR value is 11, it indicatesSR_DELAY and M=M2. When the SR value is 12, it indicatesSRP_AND_NON-SRG_OBSS-PD_PROHIBITED and M=M2. A specific quantity ofvalues in the SR values 0 to 15 that are used to indicate M and aspecific numerical value of M may be set according to a specific Dopplerscenario or high-speed movement scenario, and this embodiment imposes nospecific limitation thereon.

In this embodiment of the present invention, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU may be added in one of the following fields: an MCSfield in the HE-SIG-A (the HE SU PPDU), an MCS field in the HE-SIG-B(the HE MU SU PPDU), or a SIGB MCS field in the HE-SIG-A (the HE MU SUPPDU). The MCS field includes four bits, and may indicate 16 cases (MCSvalues are 0 to 15). Currently, 802.11ax supports 12 MCSs: MCS0 toMCS11. MCS12 to MCS15 are reserved values. For details, refer to Table9.

TABLE 9 MCS Value Meaning  0-11 Indicate MCS0 to MCS11 respectively12-15 Reserved

Optionally, in an example of the present invention, the insertionfrequency of the middle preamble in the data field in the PPDU isindicated by using one or more of reserved values of the MCS field. Thismay be applicable to a downlink data transmission solution (for example,the AP transmits data to the STA in FIG. 1 ).

TABLE 10 MCS Value Meaning  0-11 Indicate MCS0 to MCS11 respectively 12M = M1 13 M = M2 14-15 Reserved

For example, Table 10 is an example of the foregoing indication method.When the MCS values are 0 to 11, the MCS values indicate correspondingMCS parameters. One or more values are randomly selected from the MCSvalues 12 to 15 to indicate M. For example, the MCS value 12 indicatesM=M1, and the MCS value 13 indicates M=M2. A specific quantity of valuesin the MCS values 12 to 15 that are used to indicate M and a specificnumerical value of M may be set according to a specific Doppler scenarioor high-speed movement scenario, and this embodiment imposes no specificlimitation thereon.

Optionally, in an example of the present invention, the insertionfrequency of the middle preamble in the data field in the PPDU isimplicitly indicated by using a parameter used to indicate an MCS in theMCS field. This may be applicable to a downlink data transmissionsolution (for example, the AP transmits data to the STA in FIG. 1 ).

TABLE 11 MCS Value Meaning 0-11 Indicate MCS0 to MCS11 respectively, andM = M1 12 MCS0, M = M2 13 MCS1, M = M2 14 MCS2, M = M2 15 MCS3, M = M2

For example, Table 11 is an example of the foregoing indication method.When the MCS values are 0 to 11, the MCS values indicate M=M1 whileindicating corresponding MCS parameters. One or more values are randomlyselected from the MCS values 12 to 15 to indicate M. For example, whenthe MCS value is 12, it indicates MCS0 and M=M2. When the MCS value is13, it indicates MCS1 and M=M2. When the MCS value is 14, it indicatesMCS2 and M=M2. When the MCS value is 15, it indicates MCS3 and M=M2. Aspecific quantity of values in the MCS values 12 to 15 that are used toindicate MCS0 to MCS11, M, and a specific numerical value of M may beset according to a specific Doppler scenario or high-speed movementscenario, and this embodiment imposes no specific limitation thereon.

It should be noted that the MCS field in the HE-SIG-A in the HE ER SUPPDU has only MCS0 to MCS2 used. One or more of the reserved values 3 to15 of the MCS field may be used to indicate M. For details, refer to theforegoing descriptions of the HE SU PPDU. For brevity of description,details are not described herein again.

Optionally, in an example of the present invention, the insertionfrequency of the middle preamble in the data field in the PPDU isindicated by using one or more of the reserved values of the SIGB MCSfield. This may be applicable to a downlink data transmission solution(for example, the AP transmits data to the STA in FIG. 1 ).

TABLE 12 SIGB MCS Value Meaning 0-5 Indicate MCS0 to MCS5 respectively 6M = M1 7 M = M2

For example, Table 12 is an example of the foregoing indication method.The HE-SIG-A of the HE MU PPDU further includes SIGB MCS and SIGB DCM.SIG-B MCS has three bits, and may indicate eight cases. SIG-B MCS values0 to ₅ are used. SIG-B MCS values 6 and ₇ are reserved values, and maybe used to indicate M. The SIGB MCS values 0 to 5 indicate correspondingMCS parameters. One or two values are selected from the MCS values 6 and7 to indicate M. For example, the SIGB MCS value 6 indicates M=M1. Forexample, the SIGB MCS value 7 indicates M=M2. A specific quantity ofvalues in the SIGB MCS values 6 and 7 that are used to indicate M and aspecific numerical value of M may be set according to a specific Dopplerscenario or high-speed movement scenario, and this embodiment imposes nospecific limitation thereon.

In this embodiment of the present invention, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU may be added in one of the following fields: acombination of an MCS field and a DCM field in the HE-SIG-A (the HE SUPPDU or the HE ER SU PPDU), a combination of an MCS field and a DCMfield in the HE-SIG-B (the HE MU SU PPDU), or a combination of a SIGBMCS field and a SIGB DCM field in the HE-SIG-A (the HE MU SU PPDU). In802.11ax, the DCM field/the SIGB DCM field is applicable to only MCS0,MCS1, MCS3, and MCS4. Other MCS values or SIGB MCS values cannot beindicated simultaneously. An unsupported combination may be escaped toindicate M.

Optionally, in an example of the present invention, the insertionfrequency of the middle preamble in the data field in the PPDU isindicated by using the combination of the MCS field and the DCM field.This may be applicable to a downlink data transmission solution (forexample, the AP transmits data to the STA in FIG. 1 ).

TABLE 13 MCS Value DCM Value Meaning 0, 1, 3, 4 0/1 Indicate MCS0, MCS1,MCS3, and MCS4 respectively for which DCM is not used/used 2, 5-11 0Indicate MCS2 and MCS5 to MCS11 for which DCM is not used 2 1 Indicate M= M1 5 1 Indicate M = M2 . . . . . . . . . 11 1 Indicate M = M8 OtherReserved

For example, Table 13 is an example of the foregoing indication method.(MCS0, DCM0/MCS1, DCM0/MCS3, DCM0/MCS4, DCM0) indicate MCS0, MCS1, MCS3,and MCS4 for which dual carrier modulation is not used. (MCS0,DCM1/MCS1, DCM1/MCS3, DCM1/MCS4, DCM1) indicate MCS0, MCS1, MCS3, andMCS4 for which dual carrier modulation is used. (MCS2/MCS5 to MCS11,DCM0) indicate MC2 and MCS5 to MCS11 for which dual carrier modulationis not used. (MCS2, DCM1) indicates M=M1. (MCS5, DCM1) only indicatesM=M2 (and does not indicate any other meaning than this). A specificquantity of values in combinations of MCS values and DCM values(MC2/MCS5 to MCS11, DCM1) that are used to indicate M and a specificnumerical value of M may be set according to a specific Doppler scenarioor high-speed movement scenario, and this embodiment imposes no specificlimitation thereon.

Optionally, in an example of the present invention, the insertionfrequency of the middle preamble in the data field in the PPDU isindicated by using the combination of the SIGB MCS field and the SIGBDCM field. This may be applicable to a downlink data transmissionsolution (for example, the AP transmits data to the STA in FIG. 1 ).

TABLE 14 SIGB MCS Value SIGB DCM Value Meaning 0, 1, 3, 4 0/1 IndicateMCS0, MCS1, MCS3, and MCS4 respectively for which DCM is not used/used2, 5-7 0 Indicate MCS2 and MCS5 for which DCM is not used 2, 5-7 1Indicate M Other Reserved

For example, Table 14 is an example of the foregoing indication method.(SIGB MCS0, SIGB DCM0/SIGB MCS1, SIGB DCM0/SIGB MCS3, SIGB DCM0/SIGBMCS4, SIGB DCM0) indicate SIGB MCS0, SIGB MCS1, SIGB MCS3, and SIGB MCS4for which dual carrier modulation is not used. (SIGB MCS0, SIGBDCM1/SIGB MCS1, SIGB DCM1/SIGB MCS3, SIGB DCM1/SIGB MCS4, SIGB DCM1)indicates SIGB MCS0, SIGB MCS1, SIGB MCS3, and SIGB MCS4 for which dualcarrier modulation is used. (SIGB MC2/SIGB MCS5 to SIGB MCS7, SIGB DCM0)indicate SIGB MC2 and SIGB MCS5 to SIGB MCS7 for which dual carriermodulation is not used. (SIGB MC2/SIGB MCS5 to SIGB MCS7, SIGB DCM0)indicate M. A specific quantity of values in combinations of SIGB MCSvalues and SIGB DCM values (SIGB MC2/SIGB MCS5 to SIGB MCS7, SIGB DCM1)that are used to indicate M and a specific numerical value of M may beset according to a specific Doppler scenario or high-speed movementscenario, and this embodiment imposes no specific limitation thereon.

In this embodiment of the present invention, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU may be added in an NSTS field in the HE-SIG-B (the HEMU SU PPDU). The NSTS field includes three bits, and indicates one spacetime stream (STS) to eight STSs. For details, refer to Table 15.

TABLE 15 NSTS Corresponding Quantity of Space Time Streams 0 A quantityof space time streams is equal to 1. 1 A quantity of space time streamsis equal to 2. 2 A quantity of space time streams is equal to 3. 3 Aquantity of space time streams is equal to 4. 4 A quantity of space timestreams is equal to 5. 5 A quantity of space time streams is equal to 6.6 A quantity of space time streams is equal to 7. 7 A quantity of spacetime streams is equal to 8.

Optionally, in an example of the present invention, the insertionfrequency of the middle preamble in the data field in the PPDU isimplicitly indicated by using a parameter used to indicate an NSTS inthe NSTS field. This may be applicable to a downlink data transmissionsolution (for example, the AP transmits data to the STA in FIG. 1 ).

TABLE 16 NSTS Corresponding Quantity of Space Time Streams and M 0 Aquantity of space time streams is equal to 1, and M = M1. 1 A quantityof space time streams is equal to 2, and M = M1. 2 A quantity of spacetime streams is equal to 1, and M = M2. 3 A quantity of space timestreams is equal to 2, and M = M2. 4 A quantity of space time streams isequal to 1, and M = M3. 5 A quantity of space time streams is equal to2, and M = M3. 6 A quantity of space time streams is equal to 1, and M =M4. 7 A quantity of space time streams is equal to 2, and M = M4.

For example, Table 16 is an example of the foregoing indication method.The NSTS value 0 indicates that the quantity of space time streams isequal to 1 and M=M1. The NSTS value 1 indicates that the quantity ofspace time streams is equal to 2 and M=M1. The NSTS value 2 indicatesthat the quantity of space time streams is equal to 1 and M=M2. The NSTSvalue 3 indicates that the quantity of space time streams is equal to 1and M=M2. The NSTS value 4 indicates that the quantity of space timestreams is equal to 1 and M=M3. The NSTS value 5 indicates that thequantity of space time streams is equal to 3 and M=M3. The NSTS value 6indicates that the quantity of space time streams is equal to 1 andM=M4. The NSTS value 7 indicates that the quantity of space time streamsis equal to 2 and M=M4.

In the Doppler scenario or the high-speed movement scenario, a channelcondition is relatively poor. Usually, the scenario is a light of sightscenario (LOS), and does not allow a relatively large quantity of spacetime streams. In this embodiment, the quantity of space time streams maybe limited to 1 or 2, and four types of M are limited. In addition, aplurality of cases such as four quantities (1, 2, 3 or 4) of space timestreams and two types of M (M1 or M2) may alternatively be set. Thequantity of space time streams and M may be set according to a specificDoppler scenario or high-speed movement scenario. This is notspecifically limited in this embodiment.

In this embodiment of the present invention, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU may be added in a combination of an MCS field and anNSTS field. The combination of the MCS field and the NSTS field may be afunction of an MCS value and an NSTS value. In addition, the MCS valueand the NSTS value have an association mapping table. It should be notedthat in this embodiment, an NSTS and an MCS respectively indicate aquantity of space time streams and a modulation and coding scheme usedfor the data part. In addition, a corresponding mapping relationship isused to implicitly indicate the insertion frequency of the middlepreamble.

Optionally, in an example of the present invention, the insertionfrequency of the middle preamble in the data field in the PPDU isindicated by using the combination of the MCS field and the NSTS field.This may be applicable to a downlink data transmission solution (forexample, the AP transmits data to the STA in FIG. 1 ).

When data is downlink data (for example, the AP transmits data to theSTA in FIG. 1 ) and the Doppler scenario or the high-speed movementscenario occurs, the Doppler field in the HE-SIG-A is set to 1 (that is,a transmission scenario of the PPDU is the Doppler scenario or thehigh-speed movement scenario). The function of the MCS value and theNSTS value is used to indicate the insertion frequency of the middlepreamble. For example, a function of an MCS value and an NSTS value inthe HE SU PPDU, the HE ER SU PPDU, or the HE MU SU PPDU is used toindicate the insertion frequency of the middle preamble in thecorresponding data field.

TABLE 17 NSTS/MCS 0 1 2 3 4 5 0 M1 M1 M1 M1 M2 M2 1 M1 M1 M1 M2 M2 M2 2M1 M1 M2 M2 M2 M2

For example, Table 17 is an example of a mapping table in the foregoingindication method. (NSTS0, MCS0) indicates M=M1, (NSTS0, MCS1) indicatesM=M1, (NSTS0, MCS2) indicates M=M1, (NSTS0, MCS3) indicates M=M1,(NSTS0, MCS4) indicates M=M2, (NSTS0, MCS5) indicates M=M2, and so on. Aspecific function relationship between an MCS value and an NSTS valueused to indicate M and a specific numerical value of M may be setaccording to a specific Doppler scenario or high-speed movementscenario, and this embodiment imposes no specific limitation thereon.

In this embodiment of the present invention, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU may be added in an RU allocation field in the HE-SIG-B(the HE MU SU PPDU). The RU allocation field includes a plurality ofreserved parts. For details, refer to Table 18.

TABLE 18 8-bit RU Allocation Indication RU Distribution Quantity ofEntries . . . 01110100-01110111 Reserved value 4 01111000-01111111Reserved value 8 . . . 11100000-11111111 Reserved value 32

Optionally, in an example of the present invention, the insertionfrequency of the middle preamble in the data field in the PPDU isindicated by using a reserved value of the RU allocation field. This maybe applicable to a downlink data transmission solution (for example, theAP transmits data to the STA in FIG. 1 ).

TABLE 19 8-bit RU Allocation Quantity Indication RU Distribution M ofEntries . . . 01110100 242 242 M = M1 1 01110101 242 242 242 242 M = M11 01110110 242 242 242 242 242 242 242 242 M = M1 1 01110111 Reservedvalue 1 01111000 242 242 M = M2 1 01111001 242 242 242 242 M = M2 101111010 242 242 242 242 242 242 242 242 M = M2 1 01111011-01111111Reserved value 8 . . . 11100000-11111111 Reserved value 32

For example, Table 19 is an example of the foregoing indication method.If the RU Allocation is 01110100, (242, 242) means that an entirebandwidth is divided into two resource blocks each having 242subcarriers, and M=M1 is indicated. If the RU Allocation is 01111000,(242, 242) means that an entire bandwidth is divided into two resourceblocks each having 242 subcarriers, and M=M2 is indicated.

According to the data transmission method provided in this embodiment ofthe present invention, the insertion frequency of the middle preamble inthe data field is indicated by using a specified field in the preamble,so as to generate and send the PPDU. In this way, in differentscenarios, the middle preamble may be inserted into the data field atdifferent frequency, thereby reducing overheads of an inserted pilot andimproving data transmission performance.

FIG. 6 is a schematic diagram of a communications system according to anembodiment of the present invention. The communications system mayinclude at least one network device 100 (only one network device isshown) and one or more terminal devices 200 connected to the networkdevice 100.

The network device 100 may be a device that can communicate with theterminal device 200. The network device 100 may be any device having awireless transmission and receiving function. The network device 100includes, but is not limited to, a base station (for example, a NodeB,an evolved NodeB, eNodeB, a base station in a fifth-generation (5G)communications system, a base station or a network device in a futurecommunications system, or an access node, a wireless relay node, or awireless backhaul node in a Wi-Fi system) or the like. Alternatively,the network device 100 may be a radio controller in a cloud radio accessnetwork (CRAN) scenario. Alternatively, the network device 100 may be anetwork device in a 5G network or a network device in a future evolvednetwork, and may also be a wearable device, an in-vehicle device, or thelike. Alternatively, the network device 100 may be a small cell, atransmission reference point (transmission reference point, TRP), or thelike. Certainly, this application is not limited thereto.

The terminal device 200 is a device having a wireless transmission andreceiving function. The terminal device 200 may be deployed on land,including an indoor or outdoor device, a handheld device, a wearabledevice, or an in-vehicle device, may be deployed at a water surface (forexample, in a ship), or may be deployed in air (for example, on anairplane, in a balloon, or on a satellite). The terminal device may be amobile phone, a tablet computer (Pad), a computer having a wirelesstransmission and receiving function, a virtual reality (VR) terminaldevice, an augmented reality (AR) terminal device, a wireless terminalrelated to industrial control, a wireless terminal related toself-driving, a wireless terminal related to remote medical, a wirelessterminal related to a smart grid, a wireless terminal related totransportation safety, a wireless terminal related to a smart city, awireless terminal related to a smart home, or the like. This embodimentof this application imposes no limitation on an application scenario.The terminal device sometimes may also be referred to as user equipment(UE), an access terminal device, a UE unit, a UE station, a mobilestation, a mobile console, a remote station, a remote terminal device, amobile device, a UE terminal device, a terminal device, a wirelesscommunications device, a UE agent, a UE apparatus, or the like.

It should be noted that in this embodiment of the present invention,terms “system” and “network” may be used interchangeably. “A pluralityof” refers to two or more. In view of this, “the plurality of” in thisembodiment of the present invention may also be understood as “at leasttwo”. The term “and/or” describes an association relationship fordescribing associated objects and represents that three relationshipsmay exist. For example, A and/or B may represent the following threecases: Only A exists, both A and B exist, and only B exists. Inaddition, the character “/” usually indicates an “or” relationshipbetween the associated objects unless specified otherwise.

The foregoing describes the solutions provided in the embodiments of thepresent invention mainly from the perspective of interaction between theSTA and the AP. It may be understood that to implement the foregoingfunctions, the STA/AP or the like includes corresponding hardwarestructures and/or software modules for implementing the variousfunctions. A person of ordinary skill in the art should be easily awarethat, with reference to the units and algorithm steps in the examplesdescribed in the embodiments disclosed in this specification, thepresent invention may be implemented by hardware or a combination ofhardware and computer software. Whether a function is performed byhardware or computer software driving hardware depends on particularapplications and design constraint conditions of the technicalsolutions. A person skilled in the art may use different methods toimplement the described functions for each particular application, butit should not be considered that the implementation goes beyond thescope of the present invention.

In the embodiments of the present invention, functional unit divisionmay be performed on the STA and the AP according to the examples of theforegoing method. For example, various functional units may be dividedaccording to the corresponding functions, or two or more functions maybe integrated into one processing unit. The integrated unit may beimplemented in a form of hardware, or may be implemented in a form of asoftware functional unit. It should be noted that the unit division inthe embodiments of the present invention is an example, and is merelylogical function division. There may be another division manner in anactual implementation.

When an integrated unit is used, FIG. 7 is a possible schematicstructural diagram of a data processing apparatus in the foregoingembodiments. As shown in FIG. 7 , a data processing apparatus 700 mayinclude a PPDU generation unit 701 and a sending unit 702.

The PPDU generation unit 701 is configured to generate a physical layerprotocol data unit PPDU. The PPDU includes a preamble field, a datafield, and a middle preamble field, and the preamble in the PPDUincludes information used to indicate an insertion frequency of themiddle preamble in the data field in the PPDU. The sending unit 702 isconfigured to send the PPDU.

The data processing apparatus 700 in this embodiment has a function ofthe STA in FIG. 5 , and may implement an action completed by the STA inFIG. 5 , so as to achieve a technical effect of the corresponding dataprocessing method. For details, refer to related descriptions of FIG. 5. For brevity of description, details are not described herein again.

FIG. 8 is a schematic structural diagram of a data processing apparatus(for example, a communications apparatus such as an access point, a basestation, a station, or a terminal, or a chip in the foregoingcommunications apparatus) according to an implementation of the presentinvention. As shown in FIG. 8 , a data processing apparatus 800 may beimplemented by using a bus 801 as a general bus system structure.Depending on specific application and an overall design constraintcondition of the data processing apparatus 800, the bus 801 may includeany quantity of interconnection buses and bridges. The bus 801 connectsvarious circuits together. The circuits include a processor 802, astorage medium 803, and a bus interface 804. Optionally, the dataprocessing apparatus 800 connects a network adapter 805 and the like byusing the bus interface 804 and the bus 801. The network adapter 805 maybe configured to: implement a signal processing function of a physicallayer in a wireless communications network, and send and receive a radiofrequency signal by using an antenna 807. A user interface 806 mayconnect to a user terminal, such as a keyboard, a display, a mouse, or ajoystick. The bus 801 may also connect other various circuits, such as atiming source, a peripheral device, a voltage regulator, or a powermanagement circuit. The circuits are well-known in the art, and are notdescribed in detail.

Alternatively, the data processing apparatus 800 may also be configuredas a general-purpose processing system, for example, known as a chip.The general-purpose processing system includes one or moremicroprocessors providing a processor function and a peripheral memoryproviding at least a part of the storage medium 803. All the circuitsare connected to other supporting circuits by using a peripheral bussystem structure.

Alternatively, the data processing apparatus 800 may be implemented byan ASIC (application-specific integrated circuit) having the processor802, the bus interface 804, and the user interface 806 and at least apart of the storage medium 803 that is integrated into a single chip.Alternatively, the data processing apparatus 800 may be implemented byone or more FPGAs (field programmable gate array), PLDs (programmablelogic device), controllers, status machines, logic gates, discretehardware components, any other suitable circuits, or any combination ofcircuits that can implement various functions described in the presentinvention.

The processor 802 is responsible for bus management and generalprocessing (including executing software stored in the storage medium803). The processor 802 may be implemented by one or moregeneral-purpose processors and/or special-purpose processors. Examplesof the processor include a microprocessor, a microcontroller, a DSPprocessor, and another circuit that can execute the software. Softwareshall be construed broadly to mean instructions, data, or anycombination thereof, whether referred to as software, firmware,middleware, microcode, hardware description language, or otherwise.

In the following figure, the storage medium 803 is separate from theprocessor 802. However, a person skilled in the art will readilyappreciate that the storage medium 803 or any part of the storage medium803 may be located outside the data processing apparatus 800. Forexample, the storage medium 803 may include a transmission line, acarrier waveform modulated by using data, and/or a computer productseparate from a wireless node. The media may be accessed by theprocessor 802 through the bus interface 804. Alternatively, the storagemedium 803 or any part of the storage medium 803 may be integrated intothe processor 802. For example, the storage medium 803 may be a cacheand/or a general-purpose register.

The processor 802 may perform the following step: generating a physicallayer protocol data unit PPDU. The PPDU includes a preamble field, adata field, and a middle preamble field, and the preamble in the PPDUincludes information used to indicate an insertion frequency of themiddle preamble in the data field in the PPDU.

The antenna 807 may perform the following step: sending the PPDU.

Alternatively, all or some of the procedures or functions may beimplemented by using software, hardware, firmware, or any combinationthereof. When software is used for implementation, all or some of theprocedures or functions may be implemented in a form of a computerprogram product. The computer program product includes one or morecomputer instructions. When the computer program instructions are loadedand executed on a computer, all or some of the procedures or functionsaccording to the embodiments of the present invention are generated. Thecomputer may be a general-purpose computer, a special-purpose computer,a computer network, or another programmable apparatus. The computerinstructions may be stored in a computer-readable storage medium or maybe transmitted from one computer-readable storage medium to anothercomputer-readable storage medium. For example, the computer instructionsmay be transmitted from a website, computer, server, or data center toanother website, computer, server, or data center in a wired (forexample, a coaxial cable, an optical fiber, or a digital subscriber line(DSL)) or wireless (for example, infrared, radio, or microwave) manner.The computer-readable storage medium may be any usable medium accessibleby a computer, or a data storage device, such as a server or a datacenter, integrating one or more usable media. The usable medium may be amagnetic medium (for example, a floppy disk, a hard disk, or a magnetictape), an optical medium (for example, a DVD), a semiconductor medium(for example, a solid state disk Solid State Disk, (SSD)), or the like.

When an integrated unit is used, FIG. 9 is a possible schematicstructural diagram of a data processing apparatus in the foregoingembodiments. As shown in FIG. 9 , a data processing apparatus 900 mayinclude a receiving unit 901.

The receiving unit 901 is configured to receive a physical layerprotocol data unit PPDU. The PPDU includes a preamble field, a datafield, and a middle preamble field, and the preamble in the PPDUincludes information used to indicate an insertion frequency of themiddle preamble in the data field in the PPDU.

The data processing apparatus 900 in this embodiment has a function ofthe STA in FIG. 5 , and may implement an action completed by the STA inFIG. 5 , so as to achieve a technical effect of the corresponding dataprocessing method. For details, refer to related descriptions of FIG. 5. For brevity of description, details are not described herein again.

FIG. 10 is a schematic structural diagram of a data processing apparatus(for example, a communications apparatus such as an access point, a basestation, a station, or a terminal, or a chip in the foregoingcommunications apparatus) according to an implementation of the presentinvention. As shown in FIG. 10 , a data processing apparatus 1000 may beimplemented by using a bus 1001 as a general bus system structure.Depending on specific application and an overall design constraintcondition of the data processing apparatus 1000, the bus 1001 mayinclude any quantity of interconnection buses and bridges. The bus 1001connects various circuits together. The circuits include a processor1002, a storage medium 1003, and a bus interface 1004. Optionally, thedata processing apparatus 1000 connects a network adapter 1005 and thelike by using the bus interface 1004 and the bus 1001. The networkadapter 1005 may be configured to: implement a signal processingfunction of a physical layer in a wireless communications network, andsend and receive a radio frequency signal by using an antenna 1007. Auser interface 1006 may connect to a user terminal, such as a keyboard,a display, a mouse, or a joystick. The bus 1001 may also connect othervarious circuits, such as a timing source, a peripheral device, avoltage regulator, or a power management circuit. The circuits arewell-known in the art, and are not described in detail.

Alternatively, the data processing apparatus 1000 may also be configuredas a general-purpose processing system, for example, known as a chip.The general-purpose processing system includes one or moremicroprocessors providing a processor function and a peripheral memoryproviding at least a part of the storage medium 1003. All the circuitsare connected to other supporting circuits by using a peripheral bussystem structure.

Alternatively, the data processing apparatus 1000 may be implemented byan ASIC (application-specific integrated circuit) having the processor1002, the bus interface 1004, and the user interface 1006 and at least apart of the storage medium 1003 that is integrated into a single chip.Alternatively, the data processing apparatus 1000 may be implemented byone or more FPGAs (field programmable gate array), PLDs (programmablelogic device), controllers, status machines, logic gate, discretehardware components, any other suitable circuits, or any combination ofcircuits that can implement various functions described in the presentinvention.

The processor 1002 is responsible for bus management and generalprocessing (including executing software stored in the storage medium1003). The processor 1002 may be implemented by one or moregeneral-purpose processors and/or special-purpose processors. Examplesof the processor include a microprocessor, a microcontroller, a DSPprocessor, and another circuit that can execute the software. Softwareshall be construed broadly to mean instructions, data, or anycombination thereof, whether referred to as software, firmware,middleware, microcode, hardware description language, or otherwise.

In the following figure, the storage medium 1003 is separate from theprocessor 1002. However, a person skilled in the art will readilyappreciate that the storage medium 1003 or any part of the storagemedium 1003 may be located outside the data processing apparatus 1000.For example, the storage medium 1003 may include a transmission line, acarrier waveform modulated by using data, and/or a computer productseparate from a wireless node. The media may be accessed by theprocessor 1002 through the bus interface 1004. Alternatively, thestorage medium 1003 or any part of the storage medium 1003 may beintegrated into the processor 1002. For example, the storage medium 1003may be a cache and/or a general-purpose register.

The antenna 1007 may perform the following step: receiving a physicallayer protocol data unit PPDU. The PPDU includes a preamble field, adata field, and a middle preamble field, and the preamble in the PPDUincludes information used to indicate an insertion frequency of themiddle preamble in the data field in the PPDU.

Alternatively, all or some of the procedures or functions may beimplemented by using software, hardware, firmware, or any combinationthereof. When software is used for implementation, all or some of theprocedures or functions may be implemented in a form of a computerprogram product. The computer program product includes one or morecomputer instructions. When the computer program instructions are loadedand executed on a computer, all or some of the procedures or functionsaccording to the embodiments of the present invention are generated. Thecomputer may be a general-purpose computer, a special-purpose computer,a computer network, or another programmable apparatus. The computerinstructions may be stored in a computer-readable storage medium or maybe transmitted from one computer-readable storage medium to anothercomputer-readable storage medium. For example, the computer instructionsmay be transmitted from a website, computer, server, or data center toanother website, computer, server, or data center in a wired (forexample, a coaxial cable, an optical fiber, or a digital subscriber line(DSL)) or wireless (for example, infrared, radio, or microwave) manner.The computer-readable storage medium may be any usable medium accessibleby a computer, or a data storage device, such as a server or a datacenter, integrating one or more usable media. The usable medium may be amagnetic medium (for example, a floppy disk, a hard disk, or a magnetictape), an optical medium (for example, a DVD), a semiconductor medium(for example, a solid state disk Solid State Disk, (SSD)), or the like.

An embodiment of the present invention provides a data processingmethod. Transmission related to a PPDU in the method may be applicableto a Doppler scenario or a high-speed movement scenario (for example,the STA transmits data to the AP in FIG. 1 ) occurred during uplinkmulti-user data transmission. That is, a trigger frame is needed totrigger and instruct TB PPDU transmission.

FIG. 11 is an interaction diagram of the data processing methodaccording to this embodiment of the present invention. The method isapplicable to the Doppler scenario or the high-speed movement scenario.An AP generates a trigger frame. The trigger frame is used to instructto generate and send a physical layer protocol data unit PPDU. The PPDUincludes a data field and a middle preamble field, and the trigger frameincludes information used to indicate an insertion frequency of themiddle preamble in the data field in the PPDU. The AP sends the triggerframe to a STA. The AP receives the PPDU sent by the STA.

For a manner of generating the trigger frame by the AP, refer to theforegoing manner of generating the PPDU by the STA. That is, informationindicating M is added to the trigger frame when the trigger frame isgenerated. Further, after receiving the trigger frame, the STA maygenerate the PPDU based on the information indicating M, and furthersend the PPDU to the AP.

In this embodiment, the information used to indicate the insertionfrequency of the middle preamble in the data field in the PPDU may beadded in one of the following fields: a Trigger Type field, a Dopplerfield, an HE-SIG-A field, a Trigger Dependent Common Info field, an MCSfield, a combination of an MCS field and a DCM field, an RU allocationfield, or an SS allocation field.

A core idea of this embodiment is setting the trigger frame as a triggerframe used in the Doppler scenario or the high-speed movement scenario.Therefore, the Trigger Type field or the Doppler field is mainly used toset a type of the trigger frame, and then another specified field isused to indicate M.

Optionally, in an example of the present invention, referring to FIG. 12, one or more of reserved values of the Trigger Type field in thetrigger frame are set to indicate that the trigger frame is a Dopplertrigger frame (the Trigger Type field includes four bits, and mayindicate 16 cases, where currently values 0 to 7 have been used, values8 to 15 are reserved values, and any one or more of the values 8 to 15may be set to indicate that the trigger frame is a Doppler triggerframe), and to indicate that the TB PPDU uses a midamble structure. Theinsertion frequency of the middle preamble in the data field in the TBPPDU is indicated by using one or more of reserved values of theHE-SIG-A field in a common field. For example, two bits 00 are used toindicate M=M1, 01 are used to indicate M=M2, 10 are used to indicateM=M3, and 11 are used to indicate M=M4.

For another example, two bits 00 are used to indicate M=M1, 01 are usedto indicate M=M2, 10 are used to indicate M=M3, and 11 are used toindicate that no midamble is inserted. In a default state, a bit in theReserved field in the HE-SIG-A is set to 1. Therefore, if all bits areset to 1, it indicates a default state. That is, no midamble isinserted.

Optionally, in an example of the present invention, referring to FIG. 13, one or more of reserved values of the Trigger Type field in thetrigger frame are set to indicate that the trigger frame is a Dopplertrigger frame, a midamble frequency indication field is added to theTrigger Dependent Common Info field in the trigger frame in a commonfield, and the insertion frequency of the middle preamble in the datafield in the TB PPDU is indicated by using the midamble frequencyindication field. Similarly, the midamble frequency indication field maybe added to a Trigger Dependent User Info field in a User Info field, toindicate the insertion frequency of the middle preamble in the datafield in the TB PPDU. The foregoing two manners are similar. For brevityof description, details are not described herein again.

Optionally, in an example of the present invention, referring to FIG. 14, one or more of reserved values of the Trigger Type field in thetrigger frame are set to indicate that the trigger frame is a Dopplertrigger frame, and the insertion frequency of the middle preamble in thedata field in the TB PPDU is indicated by using one or more of reservedvalues of the MCS field. For details, refer to related descriptions ofTable 10, and details are not described herein again.

Optionally, in an example of the present invention, referring to FIG. 15, one or more of reserved values of the Trigger Type field in thetrigger frame are set to indicate that the trigger frame is a Dopplertrigger frame, and the insertion frequency of the middle preamble in thedata field in the TB PPDU is indicated by using the combination of theMCS field and the DCM field. For details, refer to related descriptionsof Table 13, and details are not described herein again.

Optionally, in an example of the present invention, referring to FIG. 16, one or more of reserved values of the Trigger Type field in thetrigger frame are set to indicate that the trigger frame is a Dopplertrigger frame, and the insertion frequency of the middle preamble in thedata field in the TB PPDU is indicated by using a reserved value of theRU allocation field. For details, refer to related descriptions of Table19, and details are not described herein again.

Optionally, in an example of the present invention, referring to FIG. 17, one or more of reserved values of the Trigger Type field in thetrigger frame are set to indicate that the trigger frame is a Dopplertrigger frame, and the insertion frequency of the middle preamble in thedata field in the TB PPDU is implicitly indicated by using a parameterused to indicate an SS in the SS allocation field. The SS allocationfield has three bits, and indicates 8 SSs. For details, refer to Table20.

TABLE 20 Number of SS Corresponding Quantity of Space Time Streams 0 Aquantity of space time streams is equal to 1. 1 A quantity of space timestreams is equal to 2. 2 A quantity of space time streams is equal to 3.3 A quantity of space time streams is equal to 4. 4 A quantity of spacetime streams is equal to 5. 5 A quantity of space time streams is equalto 6. 6 A quantity of space time streams is equal to 7. 7 A quantity ofspace time streams is equal to 8.

Table 20 shows indication parameters and indicated meanings of the SSallocation field. An SS value in the SS allocation field is used toindicate a quantity of space time streams. A function of the SSallocation field is similar to a function of the NSTS field (Table 15),and both are used to indicate a quantity of space time streams in astandard. In this embodiment of the present invention, the SS allocationfield is escaped to indicate the insertion frequency of the middlepreamble. This is similar to the NSTS field. The SS value indicates theinsertion frequency of the middle preamble while indicating the quantityof space time streams. For details, refer to Table 21.

TABLE 21 Number of SS Corresponding Quantity of Space Time Streams and M0 A quantity of space time streams is equal to 1, and M = M1. 1 Aquantity of space time streams is equal to 2, and M = M1. 2 A quantityof space time streams is equal to 1, and M = M2. 3 A quantity of spacetime streams is equal to 2, and M = M2. 4 A quantity of space timestreams is equal to 1, and M = M3. 5 A quantity of space time streams isequal to 2, and M = M3. 6 A quantity of space time streams is equal to1, and M = M4. 7 A quantity of space time streams is equal to 2, and M =M4.

For example, Table 21 is an example of the foregoing indication method.The SS value 0 indicates that the quantity of space time streams isequal to 1 and M=M1. The SS value 1 indicates that the quantity of spacetime streams is equal to 2 and M=M1. The SS value 2 indicates that thequantity of space time streams is equal to 1 and M=M2. The SS value 3indicates that the quantity of space time streams is equal to 1 andM=M2. The SS value 4 indicates that the quantity of space time streamsis equal to 1 and M=M3. The SS value 5 indicates that the quantity ofspace time streams is equal to 3 and M=M3. The SS value 6 indicates thatthe quantity of space time streams is equal to 1 and M=M4. The SS value7 indicates that the quantity of space time streams is equal to 2 andM=M4.

In the Doppler scenario or the high-speed scenario, a channel conditionis relatively poor. Usually, the scenario is a light of sight scenario(LOS), and does not allow a relatively large quantity of space timestreams. In this embodiment, the quantity of space time streams may belimited to 1 or 2, and four types of M are limited. In addition, aplurality of cases such as two quantities (1 or 2) of space time streamsand two types of M (M1 or M2) may alternatively be set. The quantity ofspace time streams and M may be set based on a specific Doppler scenarioor high-speed movement scenario. This is not specifically limited inthis embodiment.

Optionally, in an example of the present invention, one or more ofreserved values of the Trigger Type field in the trigger frame are setto indicate that the trigger frame is a Doppler trigger frame, and theinsertion frequency of the middle preamble in the data field in the TBPPDU is implicitly indicated by using a parameter used to indicate an SSin the combination of the SS allocation field and the MCS field. The SSallocation field and the NSTS field are substantially the same. Fordetails, refer to related descriptions of Table 17, and details are notdescribed herein again.

Optionally, in an example of the present invention, referring to FIG. 18, the Doppler field in the trigger frame is set to 1 to indicate thatthe TB PPDU uses a midamble structure, and the insertion frequency ofthe middle preamble in the data field in the TB PPDU is indicated byusing one or more of reserved values of the HE-SIG-A field in a commonfield. For example, two bits 00 are used to indicate M=M1, 01 are usedto indicate M=M2, 10 are used to indicate M=M3, and 11 are used toindicate M=M₄ (or ii are used to indicate that no midamble is inserted).

Optionally, in an example of the present invention, referring to FIG. 19, the Doppler field in the trigger frame is set to 1, a midamblefrequency indication field is added to the Trigger Dependent Common Infofield in the trigger frame in a common field, and the insertionfrequency of the middle preamble is indicated by using the midamblefrequency indication field.

Optionally, in an example of the present invention, referring to FIG. 20, the Doppler field in the trigger frame is set to 1, and the insertionfrequency of the middle preamble in the data field in the TB PPDU isindicated by using one or more of reserved values of the MCS field. Fordetails, refer to related descriptions of Table 10, and details are notdescribed herein again.

Optionally, in an example of the present invention, referring to FIG. 21, the Doppler field in the trigger frame is set to 1, and the insertionfrequency of the middle preamble in the data field in the TB PPDU isindicated by using the combination of the MCS field and the DCM field.For details, refer to related descriptions of Table 13, and details arenot described herein again.

Optionally, in an example of the present invention, referring to FIG. 22, the Doppler field in the trigger frame is set to 1, and the insertionfrequency of the middle preamble in the data field in the TB PPDU isindicated by using a reserved value of the RU allocation field. Fordetails, refer to related descriptions of Table 19, and details are notdescribed herein again.

Optionally, in an example of the present invention, referring to FIG. 23, the Doppler field in the trigger frame is set to 1, and the insertionfrequency of the middle preamble in the data field in the TB PPDU isimplicitly indicated by using a parameter used to indicate an SS in theSS allocation field. For details, refer to related descriptions of Table21, and details are not described herein again.

Optionally, in an example of the present invention, the Doppler field inthe trigger frame is set to 1, and the insertion frequency of the middlepreamble in the data field in the TB

PPDU is implicitly indicated by using a parameter used to indicate an SSin the combination of the SS allocation field and the MCS field. The SSallocation field and the NSTS field are substantially the same. Fordetails, refer to related descriptions of Table 17, and details are notdescribed herein again.

Optionally, in an example of the present invention, referring to FIG. 24, the insertion frequency of the middle preamble in the data field inthe TB PPDU is indicated by using one or more of reserved values of theHE-SIG-A field. For example, two bits 00 are used to indicate M=M1, 01are used to indicate M=M2, 10 are used to indicate M=M3, and 11 are usedto indicate that no midamble is inserted.

Optionally, in an example of the present invention, referring to FIG. 25, the insertion frequency of the middle preamble in the data field inthe TB PPDU is indicated by using a reserved value of the Reserved field(one bit) in a User Info field. For example, when the value of reservedfield is equal to 1, it indicates M=M1. When the value of reserved fieldis equal to 0, it indicates M=M2.

According to the data processing method provided in this embodiment ofthe present invention, the insertion frequency of the middle preamble inthe data field is indicated by using a specified field in the triggerframe. Based on the trigger frame, generation of the TB PPDU may betriggered and the insertion frequency of the middle preamble in the datafield in the TB PPDU may be indicated. In this way, in differentscenarios, the middle preamble may be inserted into the data field atdifferent frequency, thereby reducing overheads of an inserted pilot andimproving data transmission performance in a TB PPDU transmissionprocess.

The foregoing describes the solutions provided in the embodiments of thepresent invention mainly from the perspective of interaction between theSTA and the AP. It may be understood that to implement the foregoingfunctions, the STA/AP or the like includes corresponding hardwarestructures and/or software modules for implementing the variousfunctions. A person of ordinary skill in the art should be easily awarethat, with reference to the units and algorithm steps in the examplesdescribed in the embodiments disclosed in this specification, thepresent invention may be implemented by hardware or a combination ofhardware and computer software. Whether a function is performed byhardware or computer software driving hardware depends on particularapplications and design constraint conditions of the technicalsolutions. A person skilled in the art may use different methods toimplement the described functions for each particular application, butit should not be considered that the implementation goes beyond thescope of the present invention.

In the embodiments of the present invention, functional unit divisionmay be performed on the STA and the AP according to the examples of theforegoing method. For example, various functional units may be dividedaccording to the corresponding functions, or two or more functions maybe integrated into one processing unit. The integrated unit may beimplemented in a form of hardware, or may be implemented in a form of asoftware functional unit. It should be noted that the unit division inthe embodiments of the present invention is an example, and is merelylogical function division. There may be another division manner in anactual implementation.

When an integrated unit is used, FIG. 26 is a possible schematicstructural diagram of a data processing apparatus in the foregoingembodiments. As shown in FIG. 26 , a data processing apparatus 2600 mayinclude a trigger frame generation unit 2601 and a sending unit 2602.

The trigger frame generation unit 2601 is configured to generate atrigger frame. The trigger frame is used to instruct to generate andsend a physical layer protocol data unit PPDU, the PPDU includes a datafield and a middle preamble field, and the trigger frame includesinformation used to indicate an insertion frequency of the middlepreamble in the data field in the PPDU. The sending unit 2602 isconfigured to send the trigger frame.

The data processing apparatus 2600 in this embodiment has a function ofthe AP in FIG. 11 , and may implement an action completed by the AP inFIG. 11 , so as to achieve a technical effect of the corresponding dataprocessing method. For details, refer to related descriptions of FIG. 11. For brevity of description, details are not described herein again.

FIG. 27 is a schematic structural diagram of a data processing apparatus(for example, a communications apparatus such as an access point, a basestation, a station, or a terminal, or a chip in the foregoingcommunications apparatus) according to an implementation of the presentinvention. As shown in FIG. 27 , a data processing apparatus 2700 may beimplemented by using a bus 2701 as a general bus system structure.Depending on specific application and an overall design constraintcondition of the data processing apparatus 2700, the bus 2701 mayinclude any quantity of interconnection buses and bridges. The bus 2701connects various circuits together. The circuits include a processor2702, a storage medium 2703, and a bus interface 2704. Optionally, thedata processing apparatus 2700 connects a network adapter 2705 and thelike by using the bus interface 2704 and the bus 2701. The networkadapter 2705 may be configured to: implement a signal processingfunction of a physical layer in a wireless communications network, andsend and receive a radio frequency signal by using an antenna 2707. Auser interface 2706 may connect to a user terminal, such as a keyboard,a display, a mouse, or a joystick. The bus 2701 may also connect othervarious circuits, such as a timing source, a peripheral device, avoltage regulator, or a power management circuit. The circuits arewell-known in the art, and are not described in detail.

Alternatively, the data processing apparatus 2700 may also be configuredas a general-purpose processing system, for example, known as a chip.The general-purpose processing system includes one or moremicroprocessors providing a processor function and a peripheral memoryproviding at least a part of the storage medium 2703. All the circuitsare connected to other supporting circuits by using a peripheral bussystem structure.

Alternatively, the data processing apparatus 2700 may be implemented byan ASIC (application-specific integrated circuit) having the processor2702, the bus interface 2704, and the user interface 2706 and at least apart of the storage medium 2703 that is integrated into a single chip.Alternatively, the data processing apparatus 2700 may be implemented byone or more FPGAs (field programmable gate array), PLDs (programmablelogic device), controllers, status machines, gate logics, discretehardware components, any other suitable circuits, or any combination ofcircuits that can implement various functions described in the presentinvention.

The processor 2702 is responsible for bus management and generalprocessing (including executing software stored in the storage medium2703). The processor 2702 may be implemented by one or moregeneral-purpose processors and/or special-purpose processors. Examplesof the processor include a microprocessor, a microcontroller, a DSPprocessor, and another circuit that can execute the software. Softwareshall be construed broadly to mean instructions, data, or anycombination thereof, whether referred to as software, firmware,middleware, microcode, hardware description language, or otherwise.

In the following figure, the storage medium 2703 is separate from theprocessor 2702. However, a person skilled in the art will readilyappreciate that the storage medium 2703 or any part of the storagemedium 2703 may be located outside the data processing apparatus 2700.For example, the storage medium 2703 may include a transmission line, acarrier waveform modulated by using data, and/or a computer productseparate from a wireless node. The media may be accessed by theprocessor 2702 through the bus interface 2704. Alternatively, thestorage medium 2703 or any part of the storage medium 2703 may beintegrated into the processor 2702. For example, the storage medium 2703may be a cache and/or a general-purpose register.

The processor 2702 may perform the following step: generating a triggerframe. The trigger frame is used to instruct to generate and send aphysical layer protocol data unit PPDU, the PPDU includes a data fieldand a middle preamble field, and the trigger frame includes informationused to indicate an insertion frequency of the middle preamble in thedata field in the PPDU.

The antenna 2707 may perform the following step: sending the triggerframe.

Alternatively, all or some of the procedures or functions may beimplemented by using software, hardware, firmware, or any combinationthereof. When software is used for implementation, all or some of theprocedures or functions may be implemented in a form of a computerprogram product. The computer program product includes one or morecomputer instructions. When the computer program instructions are loadedand executed on a computer, all or some of the procedures or functionsaccording to the embodiments of the present invention are generated. Thecomputer may be a general-purpose computer, a special-purpose computer,a computer network, or another programmable apparatus. The computerinstructions may be stored in a computer-readable storage medium or maybe transmitted from one computer-readable storage medium to anothercomputer-readable storage medium. For example, the computer instructionsmay be transmitted from a website, computer, server, or data center toanother website, computer, server, or data center in a wired (forexample, a coaxial cable, an optical fiber, or a digital subscriber line(DSL)) or wireless (for example, infrared, radio, or microwave) manner.The computer-readable storage medium may be any usable medium accessibleby a computer, or a data storage device, such as a server or a datacenter, integrating one or more usable media. The usable medium may be amagnetic medium (for example, a floppy disk, a hard disk, or a magnetictape), an optical medium (for example, a DVD), a semiconductor medium(for example, a solid state disk (SSD)), or the like.

When an integrated unit is used, FIG. 28 is a possible schematicstructural diagram of a data processing apparatus in the foregoingembodiments. As shown in FIG. 28 , a data processing apparatus 2800 mayinclude a receiving unit 2801, a PPDU generation unit 2802, and asending unit 2803.

The receiving unit 2801 is configured to receive a trigger frame. Thetrigger frame is used to instruct to generate and send a physical layerprotocol data unit PPDU, the trigger frame includes information used toindicate an insertion frequency of a middle preamble in a data field inthe PPDU, and the PPDU includes the data field and the middle preamblefield. The PPDU generation unit 2802 is configured to generate the PPDUbased on the trigger frame. The sending unit 2803 is configured to sendthe PPDU.

The data processing apparatus 2800 in this embodiment has a function ofthe STA in FIG. 11 , and may implement an action completed by the STA inFIG. 11 , so as to achieve a technical effect of the corresponding dataprocessing method. For details, refer to related descriptions of FIG. 11. For brevity of description, details are not described herein again.

FIG. 29 is a schematic structural diagram of a data processing apparatus(for example, a communications apparatus such as an access point, a basestation, a station, or a terminal, or a chip in the foregoingcommunications apparatus) according to an implementation of the presentinvention. As shown in FIG. 29 , a data processing apparatus 2900 may beimplemented by using a bus 2901 as a general bus system structure.Depending on specific application and an overall design constraintcondition of the data processing apparatus 2900, the bus 2901 mayinclude any quantity of interconnection buses and bridges. The bus 2901connects various circuits together. The circuits include a processor2902, a storage medium 2903, and a bus interface 2904. Optionally, thedata processing apparatus 2900 connects a network adapter 2905 and thelike by using the bus interface 2904 and the bus 2901. The networkadapter 2905 may be configured to: implement a signal processingfunction of a physical layer in a wireless communications network, andsend and receive a radio frequency signal by using an antenna 2907. Auser interface 2906 may connect to a user terminal, such as a keyboard,a display, a mouse, or a joystick. The bus 2901 may also connect othervarious circuits, such as a timing source, a peripheral device, avoltage regulator, or a power management circuit. The circuits arewell-known in the art, and are not described in detail.

Alternatively, the data processing apparatus 2900 may also be configuredas a general-purpose processing system, for example, known as a chip.The general-purpose processing system includes one or moremicroprocessors providing a processor function and a peripheral memoryproviding at least a part of the storage medium 2903. All the circuitsare connected to other supporting circuits by using a peripheral bussystem structure.

Alternatively, the data processing apparatus 2900 may be implemented byan ASIC (application-specific integrated circuit) having the processor2902, the bus interface 2904, and the user interface 2906 and at least apart of the storage medium 2903 that is integrated into a single chip.Alternatively, the data processing apparatus 2900 may be implemented byone or more FPGAs (field programmable gate array), PLDs (programmablelogic device), controllers, status machines, gate logics, discretehardware components, any other suitable circuits, or any combination ofcircuits that can implement various functions described in the presentinvention.

The processor 2902 is responsible for bus management and generalprocessing (including executing software stored in the storage medium2903). The processor 2902 may be implemented by one or moregeneral-purpose processors and/or special-purpose processors. Examplesof the processor include a microprocessor, a microcontroller, a DSPprocessor, and another circuit that can execute the software. Softwareshall be construed broadly to mean instructions, data, or anycombination thereof, whether referred to as software, firmware,middleware, microcode, hardware description language, or otherwise.

In the following figure, the storage medium 2903 is separate from theprocessor 2902. However, a person skilled in the art will readilyappreciate that the storage medium 2903 or any part of the storagemedium 2903 may be located outside the data processing apparatus 2900.For example, the storage medium 2903 may include a transmission line, acarrier waveform modulated by using data, and/or a computer productseparate from a wireless node. The media may be accessed by theprocessor 2902 through the bus interface 2904. Alternatively, thestorage medium 2903 or any part of the storage medium 2903 may beintegrated into the processor 2902. For example, the storage medium 2903may be a cache and/or a general-purpose register.

The antenna 2907 may perform the following step: receiving a triggerframe. The trigger frame is used to instruct to generate and send aphysical layer protocol data unit PPDU, the trigger frame includesinformation used to indicate an insertion frequency of a middle preamblein a data field in the PPDU, and the PPDU includes the data field andthe middle preamble field.

The processor 2902 may perform the following step: generating the PPDUbased on the trigger frame.

The antenna 2907 may perform the following step: sending the PPDU.

Alternatively, all or some of the procedures or functions may beimplemented by using software, hardware, firmware, or any combinationthereof. When software is used for implementation, all or some of theprocedures or functions may be implemented in a form of a computerprogram product. The computer program product includes one or morecomputer instructions. When the computer program instructions are loadedand executed on a computer, all or some of the procedures or functionsaccording to the embodiments of the present invention are generated. Thecomputer may be a general-purpose computer, a special-purpose computer,a computer network, or another programmable apparatus. The computerinstructions may be stored in a computer-readable storage medium or maybe transmitted from one computer-readable storage medium to anothercomputer-readable storage medium. For example, the computer instructionsmay be transmitted from a website, computer, server, or data center toanother website, computer, server, or data center in a wired (forexample, a coaxial cable, an optical fiber, or a digital subscriber line(DSL)) or wireless (for example, infrared, radio, or microwave) manner.The computer-readable storage medium may be any usable medium accessibleby a computer, or a data storage device, such as a server or a datacenter, integrating one or more usable media. The usable medium may be amagnetic medium (for example, a floppy disk, a hard disk, or a magnetictape), an optical medium (for example, a DVD), a semiconductor medium(for example, a solid state disk (SSD)), or the like.

An embodiment of the present invention provides a data processingmethod. Transmission related to a PPDU may be applicable to a Dopplerscenario or a high-speed movement scenario (for example, the STAtransmits data to the AP in FIG. 1 ) occurred during uplink datatransmission. In other words, a MAC frame is needed to trigger andinstruct TB PPDU transmission.

FIG. 30 is an interaction diagram of the data processing methodaccording to this embodiment of the present invention. The method isapplicable to the Doppler scenario or the high-speed movement scenario.An AP generates a Media Access Control MAC frame. The MAC frame is usedto instruct to generate and send a physical layer protocol data unitPPDU. The PPDU includes a data field and a middle preamble field, andthe MAC frame includes information used to indicate an insertionfrequency of the middle preamble in the data field in the PPDU. The APsends the MAC frame to the STA. The AP receives the PPDU sent by theSTA.

For a process of interaction between the AP and the STA, refer todescriptions of FIG. 11 , and details are not described herein again.

The information used to indicate the insertion frequency of the middlepreamble in the data field in the PPDU is added in a high throughputcontrol (HTC) field in the MAC frame. The HTC field includes thefollowing fields. For details, refer to FIG. 31 .

Optionally, in an example of the present invention, referring to FIG. 32, the insertion frequency of the middle preamble in the data field inthe TB PPDU is indicated by using a reserved value of an RU allocationfield. For details, refer to related descriptions of Table 18, anddetails are not described herein again.

Optionally, in an example of the present invention, referring to FIG. 33, the insertion frequency of the middle preamble in the data field inthe TB PPDU is indicated by using one or more of reserved values of a ULMCS field. For details, refer to related descriptions of Table 10, anddetails are not described herein again.

Optionally, in an example of the present invention, referring to FIG. 34, the insertion frequency of the middle preamble in the data field inthe TB PPDU is indicated by using one or more of reserved values of aReserved field. For details, refer to related descriptions of FIG. 17 ,and details are not described herein again.

According to the data processing method provided in this embodiment ofthe present invention, the insertion frequency of the middle preamble isindicated by using a specified field in the MAC frame. Based on the MACframe, the TB PPDU may be triggered and the insertion frequency of themiddle preamble in the data field in the TB PPDU may be indicated. Inthis way, in different scenarios, the middle preamble may be insertedinto the data field at different frequency, thereby reducing overheadsof an inserted pilot and improving data transmission performance in aPPDU transmission process.

The foregoing describes the solutions provided in the embodiments of thepresent invention mainly from the perspective of interaction between theSTA and the AP. It may be understood that to implement the foregoingfunctions, the STA/AP or the like includes corresponding hardwarestructures and/or software modules for implementing the variousfunctions. A person of ordinary skill in the art should be easily awarethat, with reference to the units and algorithm steps in the examplesdescribed in the embodiments disclosed in this specification, thepresent invention may be implemented by hardware or a combination ofhardware and computer software. Whether a function is performed byhardware or computer software driving hardware depends on particularapplications and design constraint conditions of the technicalsolutions. A person skilled in the art may use different methods toimplement the described functions for each particular application, butit should not be considered that the implementation goes beyond thescope of the present invention.

In the embodiments of the present invention, functional unit divisionmay be performed on the STA and the AP according to the examples of theforegoing method. For example, various functional units may be dividedaccording to the corresponding functions, or two or more functions maybe integrated into one processing unit. The integrated unit may beimplemented in a form of hardware, or may be implemented in a form of asoftware functional unit. It should be noted that the unit division inthe embodiments of the present invention is an example, and is merelylogical function division. There may be another division manner in anactual implementation.

When an integrated unit is used, FIG. 35 is a possible schematicstructural diagram of a data processing apparatus in the foregoingembodiments. As shown in FIG. 35 , a data processing apparatus 3500 mayinclude a MAC frame generation unit 3501 and a sending unit 3502.

The MAC frame generation unit 3501 is configured to generate a MediaAccess Control MAC frame. The MAC frame is used to instruct to generateand send a physical layer protocol data unit PPDU, the PPDU includes adata field and a middle preamble field, and the MAC frame includesinformation used to indicate an insertion frequency of the middlepreamble in the data field in the PPDU. The sending unit 3502 isconfigured to send the MAC frame.

The data processing apparatus 3500 in this embodiment has a function ofthe AP in FIG. 30 , and may implement an action completed by the AP inFIG. 30 , so as to achieve a technical effect of the corresponding dataprocessing method. For details, refer to related descriptions of FIG. 30. For brevity of description, details are not described herein again.

FIG. 36 is a schematic structural diagram of a data processing apparatus(for example, a communications apparatus such as an access point, a basestation, a station, or a terminal, or a chip in the foregoingcommunications apparatus) according to an implementation of the presentinvention. As shown in FIG. 36 , a data processing apparatus 3600 may beimplemented by using a bus 3601 as a general bus system structure.Depending on specific application and an overall design constraintcondition of the data processing apparatus 3600, the bus 3601 mayinclude any quantity of interconnection buses and bridges. The bus 3601connects various circuits together. The circuits include a processor3602, a storage medium 3603, and a bus interface 3604. Optionally, thedata processing apparatus 3600 connects a network adapter 3605 and thelike by using the bus interface 3604 and the bus 3601. The networkadapter 3605 may be configured to: implement a signal processingfunction of a physical layer in a wireless communications network, andsend and receive a radio frequency signal by using an antenna 3607. Auser interface 3606 may connect to a user terminal, such as a keyboard,a display, a mouse, or a joystick. The bus 3601 may also connect othervarious circuits, such as a timing source, a peripheral device, avoltage regulator, or a power management circuit. The circuits arewell-known in the art, and are not described in detail.

Alternatively, the data processing apparatus 3600 may also be configuredas a general-purpose processing system, for example, known as a chip.The general-purpose processing system includes one or moremicroprocessors providing a processor function and a peripheral memoryproviding at least a part of the storage medium 3603. All the circuitsare connected to other supporting circuits by using a peripheral bussystem structure.

Alternatively, the data processing apparatus 3600 may be implemented byan ASIC (application-specific integrated circuit) having the processor3602, the bus interface 3604, and the user interface 3606 and at least apart of the storage medium 3603 that is integrated into a single chip.Alternatively, the data processing apparatus 3600 may be implemented byone or more FPGAs (field programmable gate array), PLDs (programmablelogic device), controllers, status machines, gate logics, discretehardware components, any other suitable circuits, or any combination ofcircuits that can implement various functions described in the presentinvention.

The processor 3602 is responsible for bus management and generalprocessing (including executing software stored in the storage medium3603). The processor 3602 may be implemented by one or moregeneral-purpose processors and/or special-purpose processors. Examplesof the processor include a microprocessor, a microcontroller, a DSPprocessor, and another circuit that can execute the software. Softwareshall be construed broadly to mean instructions, data, or anycombination thereof, whether referred to as software, firmware,middleware, microcode, hardware description language, or otherwise.

In the following figure, the storage medium 3603 is separate from theprocessor 3602. However, a person skilled in the art will readilyappreciate that the storage medium 3603 or any part of the storagemedium 3603 may be located outside the data processing apparatus 3600.For example, the storage medium 3603 may include a transmission line, acarrier waveform modulated by using data, and/or a computer productseparate from a wireless node. The media may be accessed by theprocessor 3602 through the bus interface 3604. Alternatively, thestorage medium 3603 or any part of the storage medium 3603 may beintegrated into the processor 3602. For example, the storage medium 3603may be a cache and/or a general-purpose register.

The processor 3602 may perform the following step: generating a MediaAccess Control MAC frame. The MAC frame is used to instruct to generateand send a physical layer protocol data unit PPDU, the PPDU includes adata field and a middle preamble field, and the MAC frame includesinformation used to indicate an insertion frequency of the middlepreamble in the data field in the PPDU.

The antenna 3607 may perform the following step: sending the MAC frame.

Alternatively, all or some of the procedures or functions may beimplemented by using software, hardware, firmware, or any combinationthereof. When software is used for implementation, all or some of theprocedures or functions may be implemented in a form of a computerprogram product. The computer program product includes one or morecomputer instructions. When the computer program instructions are loadedand executed on a computer, all or some of the procedures or functionsaccording to the embodiments of the present invention are generated. Thecomputer may be a general-purpose computer, a special-purpose computer,a computer network, or another programmable apparatus. The computerinstructions may be stored in a computer-readable storage medium or maybe transmitted from one computer-readable storage medium to anothercomputer-readable storage medium. For example, the computer instructionsmay be transmitted from a website, computer, server, or data center toanother website, computer, server, or data center in a wired (forexample, a coaxial cable, an optical fiber, or a digital subscriber line(DSL)) or wireless (for example, infrared, radio, or microwave) manner.The computer-readable storage medium may be any usable medium accessibleby a computer, or a data storage device, such as a server or a datacenter, integrating one or more usable media. The usable medium may be amagnetic medium (for example, a floppy disk, a hard disk, or a magnetictape), an optical medium (for example, a DVD), a semiconductor medium(for example, a solid state disk (SSD)), or the like.

When an integrated unit is used, FIG. 37 is a possible schematicstructural diagram of a data processing apparatus in the foregoingembodiments. As shown in FIG. 37 , a data processing apparatus 3700 mayinclude a receiving unit 3701, a PPDU generation unit 3702, and asending unit 3703.

The receiving unit 3701 is configured to receive a Media Access ControlMAC frame. The MAC frame is used to instruct to generate and send aphysical layer protocol data unit PPDU, the PPDU includes a data fieldand a middle preamble field, and the MAC frame includes information usedto indicate an insertion frequency of the middle preamble in the datafield in the PPDU. The PPDU generation unit 3702 is configured togenerate the PPDU based on the MAC frame. The sending unit 3703 isconfigured to send the PPDU.

The data processing apparatus 3700 in this embodiment has a function ofthe STA in FIG. 30 , and may implement an action completed by the STA inFIG. 30 , so as to achieve a technical effect of the corresponding dataprocessing method. For details, refer to related descriptions of FIG. 30. For brevity of description, details are not described herein again.

FIG. 38 is a schematic structural diagram of a data processing apparatus(for example, a communications apparatus such as an access point, a basestation, a station, or a terminal, or a chip in the foregoingcommunications apparatus) according to an implementation of the presentinvention. As shown in FIG. 38 , a data processing apparatus 3800 may beimplemented by using a bus 3801 as a general bus system structure.Depending on specific application and an overall design constraintcondition of the data processing apparatus 3800, the bus 3801 mayinclude any quantity of interconnection buses and bridges. The bus 3801connects various circuits together. The circuits include a processor3802, a storage medium 3803, and a bus interface 3804. Optionally, thedata processing apparatus 3800 connects a network adapter 3805 and thelike by using the bus interface 3804 and the bus 3801. The networkadapter 3805 may be configured to: implement a signal processingfunction of a physical layer in a wireless communications network, andsend and receive a radio frequency signal by using an antenna 3807. Auser interface 3806 may connect to a user terminal, such as a keyboard,a display, a mouse, or a joystick. The bus 3801 may also connect othervarious circuits, such as a timing source, a peripheral device, avoltage regulator, or a power management circuit. The circuits arewell-known in the art, and are not described in detail.

Alternatively, the data processing apparatus 3800 may also be configuredas a general-purpose processing system, for example, known as a chip.The general-purpose processing system includes one or moremicroprocessors providing a processor function and a peripheral memoryproviding at least a part of the storage medium 3803. All the circuitsare connected to other supporting circuits by using a peripheral bussystem structure.

Alternatively, the data processing apparatus 3800 may be implemented byan ASIC (application-specific integrated circuit) having the processor3802, the bus interface 3804, and the user interface 3806 and at least apart of the storage medium 3803 that is integrated into a single chip.Alternatively, the data processing apparatus 3800 may be implemented byone or more FPGAs (field programmable gate array), PLDs (programmablelogic device), controllers, status machines, gate logics, discretehardware components, any other suitable circuits, or any combination ofcircuits that can implement various functions described in the presentinvention.

The processor 3802 is responsible for bus management and generalprocessing (including executing software stored in the storage medium3803). The processor 3802 may be implemented by one or moregeneral-purpose processors and/or special-purpose processors. Examplesof the processor include a microprocessor, a microcontroller, a DSPprocessor, and another circuit that can execute the software. Softwareshall be construed broadly to mean instructions, data, or anycombination thereof, whether referred to as software, firmware,middleware, microcode, hardware description language, or otherwise.

In the following figure, the storage medium 3803 is separate from theprocessor 3802. However, a person skilled in the art will readilyappreciate that the storage medium 3803 or any part of the storagemedium 3803 may be located outside the data processing apparatus 3800.For example, the storage medium 3803 may include a transmission line, acarrier waveform modulated by using data, and/or a computer productseparate from a wireless node. The media may be accessed by theprocessor 3802 through the bus interface 3804. Alternatively, thestorage medium 3803 or any part of the storage medium 3803 may beintegrated into the processor 3802. For example, the storage medium 3803may be a cache and/or a general-purpose register.

The antenna 3807 may perform the following step: receiving a MediaAccess Control MAC frame. The MAC frame is used to instruct to generateand send a physical layer protocol data unit PPDU, the PPDU includes adata field and a middle preamble field, and the MAC frame includesinformation used to indicate an insertion frequency of the middlepreamble in the data field in the PPDU.

The processor 3802 may perform the following step: generating the PPDUbased on the MAC frame.

The antenna 3807 may perform the following step: sending the PPDU.

Alternatively, all or some of the procedures or functions may beimplemented by using software, hardware, firmware, or any combinationthereof. When software is used for implementation, all or some of theprocedures or functions may be implemented in a form of a computerprogram product. The computer program product includes one or morecomputer instructions. When the computer program instructions are loadedand executed on a computer, all or some of the procedures or functionsaccording to the embodiments of the present invention are generated. Thecomputer may be a general-purpose computer, a special-purpose computer,a computer network, or another programmable apparatus. The computerinstructions may be stored in a computer-readable storage medium or maybe transmitted from one computer-readable storage medium to anothercomputer-readable storage medium. For example, the computer instructionsmay be transmitted from a website, computer, server, or data center toanother website, computer, server, or data center in a wired (forexample, a coaxial cable, an optical fiber, or a digital subscriber line(DSL)) or wireless (for example, infrared, radio, or microwave) manner.The computer-readable storage medium may be any usable medium accessibleby a computer, or a data storage device, such as a server or a datacenter, integrating one or more usable media. The usable medium may be amagnetic medium (for example, a floppy disk, a hard disk, or a magnetictape), an optical medium (for example, a DVD), a semiconductor medium(for example, a solid state disk (SSD)), or the like.

A person skilled in the art may be further aware that, in combinationwith the examples described in the embodiments disclosed in thisspecification, units and algorithm steps may be implemented byelectronic hardware, computer software, or a combination thereof. Toclearly describe the interchangeability between the hardware and thesoftware, the foregoing has described compositions and steps of eachexample in general according to functions. Whether the functions areperformed by hardware or software depends on particular applications anddesign constraint conditions of the technical solutions. A personskilled in the art may use different methods to implement the describedfunctions for each particular application, but it should not beconsidered that the implementation goes beyond the scope of the presentinvention.

The steps in the method or algorithm described in the embodimentsdisclosed in this specification may be implemented by hardware, softwaremodule executed by the processor, or combination of hardware andsoftware. The software module may reside in a random-access memory(RAM), a memory, a read-only memory (ROM), an electrically programmableROM, an electrically erasable programmable ROM, a register, a hard disk,a removable disk, a CD-ROM, or any other form of storage medium known inthe art.

In the foregoing specific implementations, the objective, technicalsolutions, and benefits of the present invention are further describedin detail. It should be understood that the foregoing descriptions aremerely specific implementations of the present invention, but are notintended to limit the protection scope of the present invention. Anymodification, equivalent replacement, or improvement made withoutdeparting from the principle of the present invention should fall withinthe protection scope of the present invention.

An embodiment of the present invention discloses A1. A data processingmethod, including: generating a physical layer protocol data unit PPDU,where the PPDU includes a preamble field, a data field, and a middlepreamble field, and the preamble in the PPDU includes information usedto indicate an insertion frequency of the middle preamble in the datafield in the PPDU; and sending the PPDU.

A2. According to the method described in A1, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in one of the following fields: an SR fieldused to indicate a parameter related to spatial reuse in a highefficient signal field A HE-SIG-A, an MCS field used to indicate amodulation and coding scheme in the HE-SIG-A, an MCS field in a highefficient signal field B HE-SIG-B, a SIGB MCS field used to indicate ahigh efficient signal field B modulation and coding scheme in theHE-SIG-A, a combination of an MCS field and a DCM field in the HE-SIG-A,a combination of an MCS field and a DCM field in the HE-SIG-B, acombination of a SIGB MCS field and a SIGB DCM field in the HE-SIG-A, anNSTS field used to indicate a quantity of space time streams of a singleuser in the HE-SIG-B, a combination of an MCS field and an NSTS field,or an RU allocation field used to indicate a resource unit in theHE-SIG-B.

A3. According to the method described in A2, the insertion frequency ofthe middle preamble is indicated by using one or more of reserved valuesof the SR field.

A4. According to the method described in A2, the insertion frequency ofthe middle preamble is indicated by using one or more of reserved valuesof the MCS field or the SIGB MCS field.

A5. According to the method described in A2, the insertion frequency ofthe middle preamble is implicitly indicated by using a parameter used toindicate an MCS in the MCS field.

A6. According to the method described in A2, the insertion frequency ofthe middle preamble is indicated by using the combination of the MCSfield and the DCM field.

A7. According to the method described in A2, the insertion frequency ofthe middle preamble is indicated by using the combination of the SIGBMCS field and the SIGB DCM field.

A8. According to the method described in A2, the insertion frequency ofthe middle preamble is implicitly indicated by using a parameter used toindicate an NSTS in the NSTS field.

A9. According to the method described in A2, the insertion frequency ofthe middle preamble is indicated by using the combination of the MCSfield and the NSTS field.

A10. According to the method described in A2, the insertion frequency ofthe middle preamble is indicated by using a reserved value of the RUallocation field.

An embodiment of the present invention further discloses B11. A dataprocessing method, including: generating a trigger frame, where thetrigger frame is used to instruct to generate and send a physical layerprotocol data unit PPDU, the PPDU includes a data field and a middlepreamble field, and the trigger frame includes information used toindicate an insertion frequency of the middle preamble in the data fieldin the PPDU, and the PPDU includes the data field and the middlepreamble field; and sending the trigger frame.

B12. According to the method described in B11, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in one of the following fields: a TriggerType field used to indicate a trigger frame type, a Doppler field usedto indicate whether a Doppler mode is used for a data packet, a highefficient signal field A HE-SIG-A, a Trigger Dependent Common Info fieldfor indicating common information based on a trigger frame type, an MCSfield used to indicate a modulation and coding scheme, a combination ofan MCS field and a DCM field, an RU allocation field used to indicate aresource unit, an SS allocation field used to indicate a quantity ofspace time streams, or a combination of an SS allocation field and anMCS field in the trigger frame.

B13. According to the method described in B12, one or more of reservedvalues of the Trigger Type field in the trigger frame are set toindicate that the trigger frame is a Doppler trigger frame, and toindicate that the trigger-based PPDU uses a middle preamble midamblestructure, and the insertion frequency of the middle preamble isindicated by using one or more of reserved values of the HE-SIG-A field.

B14. According to the method described in B12, one or more of reservedvalues of the Trigger Type field in the trigger frame are set toindicate that the trigger frame is a Doppler trigger frame, a midamblefrequency indication field is added to the Trigger Dependent Common Infofield, and the insertion frequency of the middle preamble is indicatedby using the midamble frequency indication field.

B15. According to the method described in B12, one or more of reservedvalues of the Trigger Type field in the trigger frame are set toindicate that the trigger frame is a Doppler trigger frame, and theinsertion frequency of the middle preamble is indicated by using one ormore of reserved values of the MCS field.

B16. According to the method described in B12, one or more of reservedvalues of the Trigger Type field in the trigger frame are set toindicate that the trigger frame is a Doppler trigger frame, and theinsertion frequency of the middle preamble is indicated by using thecombination of the MCS field and the DCM field.

B17. According to the method described in B12, one or more of reservedvalues of the Trigger Type field in the trigger frame are set toindicate that the trigger frame is a Doppler trigger frame, and theinsertion frequency of the middle preamble is indicated by using areserved value of the RU allocation field.

B18. According to the method described in B12, one or more of reservedvalues of the Trigger Type field in the trigger frame are set toindicate that the trigger frame is a Doppler trigger frame, and theinsertion frequency of the middle preamble is implicitly indicated byusing a parameter used to indicate an SS in the SS allocation field.

B19. According to the method described in B12, one or more of reservedvalues of the Trigger Type field in the trigger frame are set toindicate that the trigger frame is a Doppler trigger frame, and theinsertion frequency of the middle preamble is implicitly indicated byusing a parameter used to indicate an SS in the combination of the SSallocation field and the MCS field.

B20. According to the method described in B12, the indicating theinsertion frequency of the middle preamble in a data field by using aspecified field in the trigger frame further includes: setting theDoppler field in the trigger frame to 1 to indicate that the TB PPDUuses a midamble structure, and indicating the insertion frequency of themiddle preamble by using one or more of reserved values of the HE-SIG-Afield.

B21. According to the method described in B12, the Doppler field in thetrigger frame is set to 1, a midamble frequency indication field isadded to the Trigger Dependent Common Info field, and the insertionfrequency of the middle preamble is indicated by using the midamblefrequency indication field.

B22. According to the method described in B12, the Doppler field in thetrigger frame is set to 1, and the insertion frequency of the middlepreamble is indicated by using one or more of reserved values of the MCSfield.

B23. According to the method described in B12, the Doppler field in thetrigger frame is set to 1, and the insertion frequency of the middlepreamble is indicated by using the combination of the MCS field and theDCM field.

B24. According to the method described in B12, the Doppler field in thetrigger frame is set to 1, and the insertion frequency of the middlepreamble is indicated by using a reserved value of the RU allocationfield.

B25. According to the method described in B12, the Doppler field in thetrigger frame is set to 1, and the insertion frequency of the middlepreamble is implicitly indicated by using a parameter used to indicatean SS in the SS allocation field.

B26. According to the method described in B12, the Doppler field in thetrigger frame is set to 1, and the insertion frequency of the middlepreamble is implicitly indicated by using a parameter used to indicatean SS in the combination of the SS allocation field and the MCS field.

B27. According to the method described in B11, the insertion frequencyof the middle preamble is indicated by using one or more of reservedvalues of the HE-SIG-A field.

B28. According to the method described in B11, the insertion frequencyof the middle preamble is indicated by using a reserved value of theReserved field.

An embodiment of the present invention further discloses C29. A dataprocessing method, including: generating a Media Access Control MACframe, where the MAC frame is used to instruct to generate and send aphysical layer protocol data unit PPDU, the PPDU includes a data fieldand a middle preamble field, and the MAC frame includes information usedto indicate an insertion frequency of the middle preamble in the datafield in the PPDU; and sending the MAC frame.

C30. According to the method described in C29, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in a high throughput control field HTC in theMAC frame, and the HTC field includes an RU allocation field used toindicate a resource unit, a UL MCS field used to indicate an uplinkmodulation and coding scheme, and a reserved value field Reserved.

C31. According to the method described in C30, the insertion frequencyof the middle preamble is indicated by using a reserved value of the RUallocation field.

C32. According to the method described in C30, the insertion frequencyof the middle preamble is indicated by using one or more of reservedvalues of the UL MCS field.

C33. According to the method described in C30, the insertion frequencyof the middle preamble is indicated by using one or more of reservedvalues of the Reserved field.

An embodiment of the present invention further discloses D34. A dataprocessing method, including: receiving a physical layer protocol dataunit PPDU, where the PPDU includes a preamble field, a data field, and amiddle preamble field, and the preamble in the PPDU includes informationused to indicate an insertion frequency of the middle preamble in thedata field in the PPDU.

D35. According to the method described in D34, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in one of the following fields: an SR fieldused to indicate a parameter related to spatial reuse in a highefficient signal field A HE-SIG-A, an MCS field used to indicate amodulation and coding scheme in the HE-SIG-A, an MCS field in a highefficient signal field B HE-SIG-B, a SIGB MCS field used to indicate ahigh efficient signal field B modulation and coding scheme in theHE-SIG-A, a combination of an MCS field and a DCM field in the HE-SIG-A,a combination of an MCS field and a DCM field in the HE-SIG-B, acombination of a SIGB MCS field and a SIGB DCM field in the HE-SIG-A, anNSTS field used to indicate a quantity of space time streams of a singleuser in the HE-SIG-B, a combination of an MCS field and an NSTS field,or an RU allocation field used to indicate a resource unit in theHE-SIG-B.

An embodiment of the present invention further discloses E36. A dataprocessing method, including: receiving a trigger frame, where thetrigger frame is used to instruct to generate and send a physical layerprotocol data unit PPDU, the trigger frame includes information used toindicate an insertion frequency of a middle preamble in a data field inthe PPDU, and the PPDU includes the data field and the middle preamblefield; generating the PPDU based on the trigger frame; and sending thePPDU.

E37. According to the method described in E36, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in one of the following fields: a TriggerType field used to indicate a trigger frame type, a Doppler field usedto indicate whether a Doppler mode is used for a data packet, a highefficient signal field A HE-SIG-A, a Trigger Dependent Common Info fieldfor indicating common information based on a trigger frame type, an MCSfield used to indicate a modulation and coding scheme, a combination ofan MCS field and a DCM field, an RU allocation field used to indicate aresource unit, an SS allocation field used to indicate a quantity ofspace time streams, or a combination of an SS allocation field and anMCS field in the trigger frame.

An embodiment of the present invention further discloses F38. A dataprocessing method, including: receiving a Media Access Control MACframe, where the MAC frame is used to instruct to generate and send aphysical layer protocol data unit PPDU, the PPDU includes a data fieldand a middle preamble field, and the MAC frame includes information usedto indicate an insertion frequency of the middle preamble in the datafield in the PPDU; and generating and sending the PPDU based on the MACframe.

F39. According to the method described in F38, the information used toindicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in a high throughput control field HTC in theMAC frame, and the HTC field includes an RU allocation field used toindicate a resource unit, a UL MCS field used to indicate an uplinkmodulation and coding scheme, and a reserved value field Reserved.

An embodiment of the present invention further discloses G40. A dataprocessing apparatus, including: a PPDU generation unit, configured togenerate a physical layer protocol data unit PPDU, where the PPDUincludes a preamble field, a data field, and a middle preamble field,and the preamble in the PPDU includes information used to indicate aninsertion frequency of the middle preamble in the data field in thePPDU; and a sending unit, configured to send the PPDU.

G41. According to the apparatus described in G40, the information usedto indicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in one of the following fields: an SR fieldused to indicate a parameter related to spatial reuse in a highefficient signal field A HE-SIG-A, an MCS field used to indicate amodulation and coding scheme in the HE-SIG-A, an MCS field in a highefficient signal field B HE-SIG-B, a SIGB MCS field used to indicate ahigh efficient signal field B modulation and coding scheme in theHE-SIG-A, a combination of an MCS field and a DCM field in the HE-SIG-A,a combination of an MCS field and a DCM field in the HE-SIG-B, acombination of a SIGB MCS field and a SIGB DCM field in the HE-SIG-A, anNSTS field used to indicate a quantity of space time streams of a singleuser in the HE-SIG-B, a combination of an MCS field and an NSTS field,or an RU allocation field used to indicate a resource unit in theHE-SIG-B.

An embodiment of the present invention further discloses H42. A dataprocessing apparatus, including: a trigger frame generation unit,configured to generate a trigger frame, where the trigger frame is usedto instruct to generate and send a physical layer protocol data unitPPDU, the PPDU includes a data field and a middle preamble field, andthe trigger frame includes information used to indicate an insertionfrequency of the middle preamble in the data field in the PPDU; and asending unit, configured to send the trigger frame.

H43. According to the apparatus described in H42, the information usedto indicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in one of the following fields: a TriggerType field used to indicate a trigger frame type, a Doppler field usedto indicate whether a Doppler mode is used for a data packet, a highefficient signal field A HE-SIG-A, a Trigger Dependent Common Info fieldfor indicating common information based on a trigger frame type, an MCSfield used to indicate a modulation and coding scheme, a combination ofan MCS field and a DCM field, an RU allocation field used to indicate aresource unit, an SS allocation field used to indicate a quantity ofspace time streams, or a combination of an SS allocation field and anMCS field in the trigger frame.

An embodiment of the present invention further discloses I44. A dataprocessing apparatus, including: a MAC frame generation unit, configuredto generate a Media Access Control MAC frame, where the MAC frame isused to instruct to generate and send a physical layer protocol dataunit PPDU, the PPDU includes a data field and a middle preamble field,and the MAC frame includes information used to indicate an insertionfrequency of the middle preamble in the data field in the PPDU; and asending unit, configured to send the MAC frame.

I45. According to the apparatus described in I44, the information usedto indicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in a high throughput control field HTC in theMAC frame, and the HTC field includes an RU allocation field used toindicate a resource unit, a UL MCS field used to indicate an uplinkmodulation and coding scheme, and a reserved value field Reserved.

An embodiment of the present invention further discloses J46. A dataprocessing apparatus, including a receiving unit, configured to receivea physical layer protocol data unit PPDU, where the PPDU includes apreamble field, a data field, and a middle preamble field, and thepreamble in the PPDU includes information used to indicate an insertionfrequency of the middle preamble in the data field in the PPDU.

J47. According to the apparatus described in J46, the information usedto indicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in one of the following fields: an SR fieldused to indicate a parameter related to spatial reuse in a highefficient signal field A HE-SIG-A, an MCS field used to indicate amodulation and coding scheme in the HE-SIG-A, an MCS field in a highefficient signal field B HE-SIG-B, a SIGB MCS field used to indicate ahigh efficient signal field B modulation and coding scheme in theHE-SIG-A, a combination of an MCS field and a DCM field in the HE-SIG-A,a combination of an MCS field and a DCM field in the HE-SIG-B, acombination of a SIGB MCS field and a SIGB DCM field in the HE-SIG-A, anNSTS field used to indicate a quantity of space time streams of a singleuser in the HE-SIG-B, a combination of an MCS field and an NSTS field,or an RU allocation field used to indicate a resource unit in theHE-SIG-B.

An embodiment of the present invention further discloses K48. A dataprocessing apparatus, including: a receiving unit, configured to receivea trigger frame, where the trigger frame is used to instruct to generateand send a physical layer protocol data unit PPDU, the trigger frameincludes information used to indicate an insertion frequency of a middlepreamble in a data field in the PPDU, and the PPDU includes the datafield and the middle preamble field; and a PPDU generation unit,configured to generate and send the PPDU based on the trigger frame.

K49. According to the apparatus described in K48, the information usedto indicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in one of the following fields: a TriggerType field used to indicate a trigger frame type, a Doppler field usedto indicate whether a Doppler mode is used for a data packet, a highefficient signal field A HE-SIG-A, a Trigger Dependent Common Info fieldfor indicating common information based on a trigger frame type, an MCSfield used to indicate a modulation and coding scheme, a combination ofan MCS field and a DCM field, an RU allocation field used to indicate aresource unit, an SS allocation field used to indicate a quantity ofspace time streams, or a combination of an SS allocation field and anMCS field in the trigger frame.

An embodiment of the present invention further discloses L50. A dataprocessing apparatus, including: a receiving unit, configured to receivea Media Access Control MAC frame, where the MAC frame is used toinstruct to generate and send a physical layer protocol data unit PPDU,the PPDU includes a data field and a middle preamble field, and the MACframe includes information used to indicate an insertion frequency ofthe middle preamble in the data field in the PPDU; and a PPDU generationunit, configured to generate and send the PPDU based on the MAC frame.

L51. According to the apparatus described in L50, the information usedto indicate the insertion frequency of the middle preamble in the datafield in the PPDU is added in a high throughput control field HTC in theMAC frame, and the HTC field includes an RU allocation field used toindicate a resource unit, a UL MCS field used to indicate an uplinkmodulation and coding scheme, and a reserved value field Reserved.

The invention claimed is:
 1. A data processing apparatus comprising: aprocessor; and a non-transitory computer-readable storage medium storinga program to be executed by the processor, the program includinginstructions for: generating a physical protocol data unit (PPDU),wherein the PPDU comprises a preamble field, a data field, and a middlepreamble field within the data field, and wherein the preamble fieldcomprises information indicating an insertion frequency of the middlepreamble field; and sending the PPDU.
 2. The apparatus according toclaim 1, wherein a Number of Space Time Stream (NSTS) field in thepreamble field indicates the insertion frequency of the middle preamblefield.
 3. The apparatus according to claim 2, wherein a first value ofthe NSTS field indicates that a quantity of space time stream is equalto 1 and the insertion frequency of the middle preamble field is M1. 4.The apparatus according to claim 2, wherein a second value of the NSTSfield indicates that a quantity of space time stream is equal to 1 andthe insertion frequency of the middle preamble field is M2.
 5. Theapparatus according to claim 1, the middle preamble field comprises ahigh efficient long training field (HE-LTF).
 6. A data processingapparatus comprising: a processor; and a non-transitorycomputer-readable storage medium storing a program to be executed by theprocessor, the program including instructions for: receiving a physicalprotocol data unit (PPDU), wherein the PPDU comprises a preamble field,a data field, and a middle preamble field within the data field, andwherein the preamble field in the PPDU comprises information indicatingan insertion frequency of the middle preamble field; obtaining theinformation indicating the insertion frequency of the middle preamblefield; and receiving the data field based on the information.
 7. Theapparatus according to claim 6, wherein a Number of Space Time Stream(NSTS) field in the preamble field indicates the insertion frequency ofthe middle preamble field.
 8. The apparatus according to claim 7,wherein a first value of the NSTS field indicates that a quantity ofspace time stream is equal to 1 and the insertion frequency of themiddle preamble field is M1.
 9. The apparatus according to claim 8,wherein receiving the data field based on the information comprises:determining that the insertion frequency of the middle preamble field isM1; receiving data of M1 symbols in the data field based on a highefficient short training field (HE-STF) and a high efficient longtraining field (HE-LTF) in the last part of the preamble field; andre-estimating a channel based on the middle preamble field, andreceiving data of M1 symbols that follow the middle preamble field. 10.The apparatus according to claim 7, wherein a second value of the NSTSfield indicates that a quantity of space time stream is equal to 1 andthe insertion frequency of the middle preamble field is M2.
 11. Theapparatus according to claim 10, wherein receiving the data field basedon the information comprises: determining that the insertion frequencyof the middle preamble field is M2; receiving data of M2 symbols in thedata field based on a high efficient short training field (HE-STF) and ahigh efficient long training field (HE-LTF) in the last part of thepreamble field; and re-estimating a channel based on the middle preamblefield, and receiving data of M2 symbols that follow the middle preamblefield.
 12. The apparatus according to claim 6, wherein the middlepreamble field comprises a high efficient long training field (HE-LTF).13. A data processing apparatus comprising: a processor; and anon-transitory computer-readable storage medium storing a program to beexecuted by the processor, the program including instructions for:receiving a physical protocol data unit (PPDU), wherein the PPDUcomprises a preamble field, a data field, and a middle preamble fieldwithin the data field, wherein the preamble field in the PPDU comprisesinformation indicating an insertion frequency of the middle preamblefield, and wherein the information indicating the one or more middlepreambles is carried in a Doppler field; obtaining the informationindicating the insertion frequency of the middle preamble field; andreceiving the data field based on the information.
 14. The apparatusaccording to claim 13, wherein a Number of Space Time Stream (NSTS)field in the preamble field indicates the insertion frequency of themiddle preamble field.
 15. The apparatus according to claim 14, whereina first value of the NSTS field indicates that a quantity of space timestream is equal to 1 and the insertion frequency of the middle preamblefield is M1.
 16. The apparatus according to claim 15, wherein receivingthe data field based on the information comprises: determining that theinsertion frequency of the middle preamble field is M1; receiving dataof M1 symbols in the data field based on a high efficient short trainingfield (HE-STF) and a high efficient long training field (HE-LTF) in thelast part of the preamble field; and re-estimating a channel based onthe middle preamble field, and receiving data of M1 symbols that followthe middle preamble field.
 17. The apparatus according to claim 14,wherein a second value of the NSTS field indicates that a quantity ofspace time stream is equal to 1 and the insertion frequency of themiddle preamble field is M2.
 18. The apparatus according to claim 17,wherein receiving the data field based on the information comprises:determining that the insertion frequency of the middle preamble field isM2; receiving data of M2 symbols in the data field based on a highefficient short training field (HE-STF) and a high efficient longtraining field (HE-LTF) in the last part of the preamble field; andre-estimating a channel based on the middle preamble field, andreceiving data of M2 symbols that follow the middle preamble field. 19.The apparatus according to claim 13, wherein the middle preamble fieldcomprises a high efficient long training field (HE-LTF).